Glean vs Vectara

Make an informed decision with our comprehensive comparison. Discover which RAG solution perfectly fits your needs.

Priyansh Khodiyar's avatar
Priyansh KhodiyarDevRel at CustomGPT.ai

Fact checked and reviewed by Bill Cava

Published: 01.04.2025Updated: 25.04.2025

In this comprehensive guide, we compare Glean and Vectara across various parameters including features, pricing, performance, and customer support to help you make the best decision for your business needs.

Overview

When choosing between Glean and Vectara, understanding their unique strengths and architectural differences is crucial for making an informed decision. Both platforms serve the RAG (Retrieval-Augmented Generation) space but cater to different use cases and organizational needs.

Quick Decision Guide

  • Choose Glean if: you value permissions-aware ai is genuinely differentiated - real-time enforcement across 100+ datasources addresses critical enterprise concern
  • Choose Vectara if: you value industry-leading accuracy with minimal hallucinations

About Glean

Glean Landing Page Screenshot

Glean is enterprise work ai with permissions-aware rag across 100+ apps. Glean is a premium enterprise RAG platform with permissions-aware AI as its core differentiator. Founded by ex-Google Search engineers, Glean achieved $100M ARR in three years and a $7.2B valuation (2025). It connects 100+ enterprise apps with real-time access controls, supports 15+ LLMs, and offers comprehensive APIs with 4-language SDKs. Trade-offs: enterprise-only sales (~$50/user/month, ~$60K minimum), no consumer messaging channels, and premium positioning over plug-and-play simplicity. Founded in 2019, headquartered in Palo Alto, CA, the platform has established itself as a reliable solution in the RAG space.

Overall Rating
96/100
Starting Price
$50/mo

About Vectara

Vectara Landing Page Screenshot

Vectara is the trusted platform for rag-as-a-service. Vectara is an enterprise-ready RAG platform that provides best-in-class retrieval accuracy with minimal hallucinations. It offers a serverless API solution for embedding powerful generative AI functionality into applications with semantic search, grounded generation, and secure access control. Founded in 2020, headquartered in Palo Alto, CA, the platform has established itself as a reliable solution in the RAG space.

Overall Rating
90/100
Starting Price
Custom

Key Differences at a Glance

In terms of user ratings, Glean in overall satisfaction. From a cost perspective, Vectara offers more competitive entry pricing. The platforms also differ in their primary focus: Enterprise RAG versus RAG Platform. These differences make each platform better suited for specific use cases and organizational requirements.

⚠️ What This Comparison Covers

We'll analyze features, pricing, performance benchmarks, security compliance, integration capabilities, and real-world use cases to help you determine which platform best fits your organization's needs. All data is independently verified from official documentation and third-party review platforms.

Detailed Feature Comparison

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Glean
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Vectara
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Data Ingestion & Knowledge Sources
  • ✅ 100+ native connectors – Cloud storage, CRM, collaboration platforms plus Indexing API
  • File formats – PDFs, Word, HTML, spreadsheets, structured data
  • Real-time sync – Content within minutes, permission changes immediate
  • ⚠️ Initial indexing – Few days depending on volume
  • Scale – 10K-100K users, hundreds of millions of documents
  • Document support – PDF, DOCX, HTML automatically indexed (Vectara Platform)
  • Auto-sync connectors – Cloud storage and enterprise system integrations keep data current
  • Embedding processing – Background conversion to embeddings enables fast semantic search
  • 1,400+ file formats – PDF, DOCX, Excel, PowerPoint, Markdown, HTML + auto-extraction from ZIP/RAR/7Z archives
  • Website crawling – Sitemap indexing with configurable depth for help docs, FAQs, and public content
  • Multimedia transcription – AI Vision, OCR, YouTube/Vimeo/podcast speech-to-text built-in
  • Cloud integrations – Google Drive, SharePoint, OneDrive, Dropbox, Notion with auto-sync
  • Knowledge platforms – Zendesk, Freshdesk, HubSpot, Confluence, Shopify connectors
  • Massive scale – 60M words (Standard) / 300M words (Premium) per bot with no performance degradation
L L M Model Options
  • ✅ 15+ LLMs supported – GPT-4, Gemini 1.5 Pro, Claude 3 Sonnet
  • Per-step model selection – Different LLMs for each workflow step
  • Temperature controls – Factual, balanced, or creative output settings
  • BYOK support – Glean Universal Key or Customer Key options
  • Automatic routing – Zero data retention, optimizes top models per query
  • Mockingbird default – In-house model with GPT-4/GPT-3.5 via Azure OpenAI available
  • Flexible selection – Choose model balancing cost versus quality for use case
  • Custom prompts – Prompt templates configurable for tone, format, citation rules
  • GPT-5.1 models – Latest thinking models (Optimal & Smart variants)
  • GPT-4 series – GPT-4, GPT-4 Turbo, GPT-4o available
  • Claude 4.5 – Anthropic's Opus available for Enterprise
  • Auto model routing – Balances cost/performance automatically
  • Zero API key management – All models managed behind the scenes
Performance & Accuracy
  • ✅ 74% human-agreement rate – 25% precision increases
  • 141% ROI over 3 years – Forrester Total Economic Impact
  • 110 hours saved per employee annually – Productivity gains
  • Hallucination prevention – RAG grounding, permissions, citations
  • ✅ Enterprise scale – Millisecond responses with heavy traffic (benchmarks)
  • ✅ Hybrid search – Semantic and keyword matching for pinpoint accuracy
  • ✅ Hallucination prevention – Advanced reranking with factual-consistency scoring
  • Sub-second responses – Optimized RAG with vector search and multi-layer caching
  • Benchmark-proven – 13% higher accuracy, 34% faster than OpenAI Assistants API
  • Anti-hallucination tech – Responses grounded only in your provided content
  • OpenGraph citations – Rich visual cards with titles, descriptions, images
  • 99.9% uptime – Auto-scaling infrastructure handles traffic spikes
Developer Experience ( A P I & S D Ks)
  • ✅ Client & Indexing APIs – Search, Chat, Agents, Documents, Governance
  • Official SDKs – Python, Java, Go, TypeScript with async support
  • Web SDK – Embeddable chat, search, autocomplete, recommendations components
  • Framework integrations – LangChain, CrewAI, OpenAI Assistants, MCP Server
  • Authentication – OAuth 2.0, user-scoped tokens, impersonation support
  • Multi-language SDKs – C#, Python, Java, JavaScript with REST API (FAQs)
  • Clear documentation – Sample code and guides for integration, indexing operations
  • Secure authentication – Azure AD or custom auth setup for API access
  • REST API – Full-featured for agents, projects, data ingestion, chat queries
  • Python SDK – Open-source customgpt-client with full API coverage
  • Postman collections – Pre-built requests for rapid prototyping
  • Webhooks – Real-time event notifications for conversations and leads
  • OpenAI compatible – Use existing OpenAI SDK code with minimal changes
Integrations & Channels
  • Slack & Teams – Official apps, Gleanbot auto-responses, Real-Time Search API
  • Browser extensions – Chrome (300K+ users), Firefox, Safari, Edge
  • ⚠️ No WhatsApp/Telegram – Designed for internal enterprise use only
  • SSO protocols – OIDC, SAML 2.0 with Okta, Microsoft Entra
  • REST APIs & SDKs – Easy integration into custom applications with comprehensive tooling
  • Embedded experiences – Search/chat widgets for websites, mobile apps, custom portals
  • Low-code connectors – Azure Logic Apps and PowerApps simplify workflow integration
  • Website embedding – Lightweight JS widget or iframe with customizable positioning
  • CMS plugins – WordPress, WIX, Webflow, Framer, SquareSpace native support
  • 5,000+ app ecosystem – Zapier connects CRMs, marketing, e-commerce tools
  • MCP Server – Integrate with Claude Desktop, Cursor, ChatGPT, Windsurf
  • OpenAI SDK compatible – Drop-in replacement for OpenAI API endpoints
  • LiveChat + Slack – Native chat widgets with human handoff capabilities
Customization & Branding
  • UI customization – Custom logos, color schemes, background images
  • Custom subdomains – your-company.glean.com
  • Chat widget styling – CSS positioning, width/height, custom containers
  • ⚠️ Limited white-labeling – Glean branding may remain visible
  • White-label control – Full theming, logos, CSS customization for brand alignment
  • Domain restrictions – Bot scope and branding configurable per deployment
  • Search UI styling – Result cards and search interface match company identity
  • Full white-labeling included – Colors, logos, CSS, custom domains at no extra cost
  • 2-minute setup – No-code wizard with drag-and-drop interface
  • Persona customization – Control AI personality, tone, response style via pre-prompts
  • Visual theme editor – Real-time preview of branding changes
  • Domain allowlisting – Restrict embedding to approved sites only
Core R A G Features
  • ✅ Hybrid search – Semantic (vector-based) + lexical (keyword) approaches
  • Knowledge Graph Framework – Proprietary anchors across enterprise data
  • LLM Control Layer – Optimizes outputs with context-aware query rewriting
  • Grounded answers – Source citations with every response
N/A
N/A
Permissions- Aware A I ( Core Differentiator)
  • ✅ Real-time access control – Across all 100+ datasources
  • Identity crawling – Users, groups, memberships, permission models
  • Connector-level mirroring – Respects native permissions (Salesforce, GDrive)
  • Zero-trust architecture – Users only see authorized content
N/A
N/A
Multi- Language & Localization
  • Full support – English, German, Japanese (semantic, assistant, UI)
  • Partial support – French, Spanish
  • 20+ languages – Early access or keyword search
N/A
N/A
Observability & Monitoring
  • Insights Dashboard – DAU/WAU/MAU, Search Session Satisfaction metrics
  • Usage metrics – Searches and chats per user per week
  • 270-day data retention – Department-level filtering
  • Audit logging – User activity, access patterns, SIEM export
  • Azure portal dashboard – Query latency, index health, usage metrics at-a-glance
  • Azure Monitor integrationAzure Monitor and App Insights for custom alerts
  • API log exports – Metrics exportable via API for compliance, analysis reports
  • Real-time dashboard – Query volumes, token usage, response times
  • Customer Intelligence – User behavior patterns, popular queries, knowledge gaps
  • Conversation analytics – Full transcripts, resolution rates, common questions
  • Export capabilities – API export to BI tools and data warehouses
Pricing & Scalability
  • ⚠️ No public pricing – Enterprise sales only
  • Estimated cost – ~$45-50+ per user/month
  • Minimum ACV – ~$60K (approximately 100 users minimum)
  • No free trial – Paid POCs up to $70K
  • Annual contracts – Per-seat model, 7-12% renewal increases, FlexCredits for premium
  • Usage-based pricing – Free tier available, bundles scale with growth (pricing)
  • Enterprise tiers – Plans scale with query volume, data size for heavy usage
  • Dedicated deployment – VPC or on-prem options for data isolation requirements
  • Standard: $99/mo – 60M words, 10 bots
  • Premium: $449/mo – 300M words, 100 bots
  • Auto-scaling – Managed cloud scales with demand
  • Flat rates – No per-query charges
Security & Privacy
  • ✅ SOC 2 Type II, ISO 27001, HIPAA, GDPR
  • ⚠️ No FedRAMP – Not for US federal government
  • AES-256 at rest, TLS 1.2+ in transit
  • Single-tenant – Isolated per customer, Cloud-Prem option
  • ✅ Data encryption – Transit and rest encryption, no model training on your content
  • ✅ Compliance certifications – SOC 2, ISO, GDPR, HIPAA (details)
  • ✅ Customer-managed keys – BYOK support with private deployments for full control
  • SOC 2 Type II + GDPR – Third-party audited compliance
  • Encryption – 256-bit AES at rest, SSL/TLS in transit
  • Access controls – RBAC, 2FA, SSO, domain allowlisting
  • Data isolation – Never trains on your data
No- Code Interface & Usability
  • ✅ Natural language configuration – Describe goals in plain language
  • Visual builder – Drag-and-drop workflow creation
  • AI-assisted creation – Auto-generates draft agents
  • 30+ prebuilt agents – Sales, engineering, IT, HR
  • Azure portal UI – Straightforward index management and settings configuration interface
  • Low-code options – PowerApps, Logic Apps connectors enable quick non-dev integration
  • ⚠️ Technical complexity – Advanced indexing tweaks require developer expertise vs turnkey tools
  • 2-minute deployment – Fastest time-to-value in the industry
  • Wizard interface – Step-by-step with visual previews
  • Drag-and-drop – Upload files, paste URLs, connect cloud storage
  • In-browser testing – Test before deploying to production
  • Zero learning curve – Productive on day one
Support & Ecosystem
  • Standard support – 24x5 via portal, email, Slack Connect
  • Premium support – 24x7 critical issues with additional fee
  • ✅ Excellent documentation – developers.glean.com with OpenAPI specs
  • GitHub repositories – SDK examples and sample projects
  • Microsoft network – Comprehensive docs, forums, technical guides backed by Microsoft
  • Enterprise support – Dedicated channels and SLA-backed help for enterprise plans
  • Azure ecosystem – Broad partner network and active developer community access
  • Comprehensive docs – Tutorials, cookbooks, API references
  • Email + in-app support – Under 24hr response time
  • Premium support – Dedicated account managers for Premium/Enterprise
  • Open-source SDK – Python SDK, Postman, GitHub examples
  • 5,000+ Zapier apps – CRMs, e-commerce, marketing integrations
Conversation & Agent Features
  • Conversation history – Thread tracking in Slack, History tab
  • Version control – All agent versions auto-saved
  • ⚠️ No lead capture – Designed for internal enterprise use
N/A
N/A
Deployment Options
  • Cloud (SaaS) – Standard Glean infrastructure deployment
  • Cloud-Prem – Customer-hosted in AWS or GCP
  • Single-tenant architecture – Isolated per customer
N/A
N/A
R A G-as-a- Service Assessment
  • ✅ TRUE RAG PLATFORM – API-first with comprehensive tools
  • Data flexibility – 100+ connectors, Indexing API
  • Best for – Large enterprises requiring permissions-aware RAG
  • Platform Type – TRUE ENTERPRISE RAG-AS-A-SERVICE: Agent OS for trusted AI
  • Core Mission – Deploy AI assistants/agents with grounded answers, safe actions, always-on governance
  • Target Market – Enterprises needing production RAG, white-label APIs, VPC/on-prem deployments
  • RAG Implementation – Mockingbird LLM (26% better than GPT-4), hybrid search, multi-stage reranking
  • API-First Architecture – REST APIs, SDKs (C#/Python/Java/JS), Azure integration (Logic Apps/Power BI)
  • Security & Compliance – SOC 2 Type 2, ISO 27001, GDPR, HIPAA, BYOK, VPC/on-prem
  • Agent-Ready Platform – Python library, Agent APIs, structured outputs, audit trails, policy enforcement
  • Advanced RAG Features – Hybrid search, reranking, HHEM scoring, multilingual retrieval (7 languages)
  • Funding – $53.5M raised ($25M Series A July 2024, FPV/Race Capital)
  • ⚠️ Enterprise complexity – Requires developer expertise for indexing, tuning, agent configuration
  • ⚠️ No no-code builder – Azure portal management but no drag-and-drop chatbot builder
  • ⚠️ Azure ecosystem focus – Best with Azure, less smooth for AWS/GCP cross-cloud flexibility
  • Use Case Fit – Mission-critical RAG, regulated industries (SOC 2/HIPAA), white-label APIs, VPC/on-prem
  • Platform type – TRUE RAG-AS-A-SERVICE with managed infrastructure
  • API-first – REST API, Python SDK, OpenAI compatibility, MCP Server
  • No-code option – 2-minute wizard deployment for non-developers
  • Hybrid positioning – Serves both dev teams (APIs) and business users (no-code)
  • Enterprise ready – SOC 2 Type II, GDPR, WCAG 2.0, flat-rate pricing
Competitive Positioning
  • ✅ Unique strength – Real-time permissions-aware AI across 100+ datasources
  • Proven ROI – 141% ROI, 110 hours/employee saved
  • ⚠️ Pricing barrier – ~$50/user/month, ~$60K minimum
  • Market position – Enterprise RAG platform between Azure AI Search and chatbot builders
  • Target customers – Enterprises needing production RAG, white-label APIs, VPC/on-prem deployments
  • Key competitors – Azure AI Search, Coveo, OpenAI Enterprise, Pinecone Assistant
  • Competitive advantages – Mockingbird LLM, hallucination detection, SOC 2/HIPAA compliance, millisecond responses
  • Pricing advantage – Usage-based with free tier, best value for enterprise RAG infrastructure
  • Use case fit – Mission-critical RAG, white-label APIs, Azure integration, high-accuracy requirements
  • Market position – Leading RAG platform balancing enterprise accuracy with no-code usability. Trusted by 6,000+ orgs including Adobe, MIT, Dropbox.
  • Key differentiators – #1 benchmarked accuracy • 1,400+ formats • Full white-labeling included • Flat-rate pricing
  • vs OpenAI – 10% lower hallucination, 13% higher accuracy, 34% faster
  • vs Botsonic/Chatbase – More file formats, source citations, no hidden costs
  • vs LangChain – Production-ready in 2 min vs weeks of development
A I Models
  • ✅ 15+ LLMs – GPT-4, Gemini 1.5 Pro, Claude 3 with per-step selection
  • Temperature controls – Factual, balanced, or creative output
  • BYOK support – Customer Key for data sovereignty
  • ✅ Mockingbird LLM – 26% better than GPT-4 on BERT F1, 0.9% hallucination rate
  • ✅ Mockingbird 2 – 7 languages (EN/ES/FR/AR/ZH/JA/KO), under 10B parameters
  • GPT-4/GPT-3.5 fallback – Azure OpenAI integration for OpenAI model preference
  • HHEM + HCM – Hughes Hallucination Evaluation with Correction Model (Mockingbird-2-Echo)
  • ✅ No training on data – Customer data never used for model training/improvement
  • Custom prompts – Templates configurable for tone, format, citation rules per domain
  • OpenAI – GPT-5.1 (Optimal/Smart), GPT-4 series
  • Anthropic – Claude 4.5 Opus/Sonnet (Enterprise)
  • Auto-routing – Intelligent model selection for cost/performance
  • Managed – No API keys or fine-tuning required
R A G Capabilities
  • ✅ Hybrid search – Semantic + lexical for accuracy
  • Knowledge Graph Framework – Proprietary anchors across data
  • 74% human-agreement – 25% precision increases
  • ✅ Hybrid search – Semantic vector + BM25 keyword matching for pinpoint accuracy
  • ✅ Advanced reranking – Multi-stage pipeline optimizes results before generation with relevance scoring
  • ✅ Factual scoring – HHEM provides reliability score for every response's grounding quality
  • ✅ Citation precision – Mockingbird outperforms GPT-4 on citation metrics, traceable to sources
  • Multilingual RAG – Cross-lingual: query/retrieve/generate in different languages (7 supported)
  • Structured outputs – Extract specific information for autonomous agent integration, deterministic data
  • GPT-4 + RAG – Outperforms OpenAI in independent benchmarks
  • Anti-hallucination – Responses grounded in your content only
  • Automatic citations – Clickable source links in every response
  • Sub-second latency – Optimized vector search and caching
  • Scale to 300M words – No performance degradation at scale
Use Cases
  • Enterprise knowledge – Unified search across 100+ datasources
  • Permissions-aware – Healthcare, finance, legal hierarchies
  • AI agents – 30+ prebuilt for sales, engineering, IT
  • Regulated industries – Health, legal, finance needing accuracy, security, SOC 2 compliance
  • Enterprise knowledge – Q&A systems with precise answers from large document repositories
  • Autonomous agents – Structured outputs for deterministic data extraction, decision-making workflows
  • White-label APIs – Customer-facing search/chat with millisecond responses at enterprise scale
  • Multilingual support – 7 languages with single knowledge base for multiple locales
  • High accuracy needs – Citation precision, factual scoring, 0.9% hallucination rate (Mockingbird-2-Echo)
  • Customer support – 24/7 AI handling common queries with citations
  • Internal knowledge – HR policies, onboarding, technical docs
  • Sales enablement – Product info, lead qualification, education
  • Documentation – Help centers, FAQs with auto-crawling
  • E-commerce – Product recommendations, order assistance
Security & Compliance
  • ✅ SOC 2 Type II, ISO 27001, HIPAA, GDPR
  • ⚠️ NO FedRAMP – Not for US federal government
  • Single-tenant – Isolated per customer, Cloud-Prem option
  • ✅ SOC 2 Type 2 – Independent audit demonstrating enterprise-grade operational security controls
  • ✅ ISO 27001 + GDPR – Information security management with EU data protection compliance
  • ✅ HIPAA ready – Healthcare compliance with BAAs available for PHI handling
  • ✅ Encryption – TLS 1.3 in transit, AES-256 at rest with BYOK support
  • ✅ Zero data retention – No model training on customer data, content stays private
  • Private deployments – VPC or on-premise for data sovereignty and network isolation
  • SOC 2 Type II + GDPR – Regular third-party audits, full EU compliance
  • 256-bit AES encryption – Data at rest; SSL/TLS in transit
  • SSO + 2FA + RBAC – Enterprise access controls with role-based permissions
  • Data isolation – Never trains on customer data
  • Domain allowlisting – Restrict chatbot to approved domains
Pricing & Plans
  • ⚠️ No public pricing – Enterprise sales only
  • ~$45-50+/user/month – Estimated cost from reports
  • ~$60K minimum ACV – Approximately 100 users minimum
  • 30-day free trial – Full enterprise feature access for evaluation before commitment
  • Usage-based pricing – Pay for query volume and data size with scalable tiers
  • Free tier – Generous free tier for development, prototyping, small production deployments
  • Enterprise pricing – Custom pricing for VPC/on-prem installations, heavy usage bundles available
  • ✅ Transparent pricing – No per-seat charges, storage surprises, or model switching fees
  • Funding – $53.5M raised ($25M Series A July 2024, FPV/Race Capital)
  • Standard: $99/mo – 10 chatbots, 60M words, 5K items/bot
  • Premium: $449/mo – 100 chatbots, 300M words, 20K items/bot
  • Enterprise: Custom – SSO, dedicated support, custom SLAs
  • 7-day free trial – Full Standard access, no charges
  • Flat-rate pricing – No per-query charges, no hidden costs
Support & Documentation
  • 24x5 standard support – Portal, email, Slack Connect
  • ✅ Excellent documentation – developers.glean.com with OpenAPI
  • Official SDKs – Python, Java, Go, TypeScript
  • Enterprise support – Dedicated channels and SLA-backed help for enterprise customers
  • Microsoft network – Extensive infrastructure, forums, technical guides backed by Microsoft
  • Comprehensive docs – API references, integration guides, SDKs at docs.vectara.com
  • Sample code – Pre-built examples, Jupyter notebooks, quick-start guides for rapid integration
  • Active community – Developer forums for peer support, knowledge sharing, best practices
  • Documentation hub – Docs, tutorials, API references
  • Support channels – Email, in-app chat, dedicated managers (Premium+)
  • Open-source – Python SDK, Postman, GitHub examples
  • Community – User community + 5,000 Zapier integrations
Limitations & Considerations
  • ⚠️ High cost barrier – ~$50/user/month, ~$60K minimum
  • ⚠️ NO FedRAMP – Not for US federal government
  • ⚠️ No consumer channels – No WhatsApp, Telegram
  • Complex implementation – Indexing takes days
  • ⚠️ Azure ecosystem focus – Best with Azure services, less smooth for AWS/GCP organizations
  • ⚠️ Developer expertise needed – Advanced indexing requires technical skills vs turnkey no-code tools
  • ⚠️ No drag-and-drop GUI – Azure portal management but no chatbot builder like Tidio/WonderChat
  • ⚠️ Limited model selection – Mockingbird/GPT-4/GPT-3.5 only, no Claude/Gemini/custom models
  • ⚠️ Sales-driven pricing – Contact sales for enterprise pricing, less transparent than self-serve platforms
  • ⚠️ Overkill for simple bots – Enterprise RAG unnecessary for basic FAQ or customer service
  • Managed service – Less control over RAG pipeline vs build-your-own
  • Model selection – OpenAI + Anthropic only; no Cohere, AI21, open-source
  • Real-time data – Requires re-indexing; not ideal for live inventory/prices
  • Enterprise features – Custom SSO only on Enterprise plan
Core Agent Features
  • ✅ Autonomous AI agents – Understand tasks, execute autonomously
  • Natural language builder – Describe goals, auto-designs workflows
  • 100+ native actions – Slack, Teams, Salesforce, Jira, GitHub
  • Agentic RAG Framework – Python library for autonomous agents: emails, bookings, system integration
  • Agent APIs (Tech Preview) – Customizable reasoning models, behavioral instructions, tool access controls
  • LlamaIndex integration – Rapid tool creation connecting Vectara corpora, single-line code generation
  • Multi-LLM support – OpenAI, Anthropic, Gemini, GROQ, Together.AI, Cohere, AWS Bedrock integration
  • Step-level audit trails – Source citations, reasoning steps, decision paths for governance compliance
  • ✅ Grounded actions – Document-grounded decisions with citations, 0.9% hallucination rate (Mockingbird-2-Echo)
  • ⚠️ Developer platform – Requires programming expertise, not for non-technical teams
  • ⚠️ No chatbot UI – No polished widgets or turnkey conversational interfaces
  • ⚠️ Tech preview status – Agent APIs subject to change before general availability
  • Custom AI Agents – Autonomous GPT-4/Claude agents for business tasks
  • Multi-Agent Systems – Specialized agents for support, sales, knowledge
  • Memory & Context – Persistent conversation history across sessions
  • Tool Integration – Webhooks + 5,000 Zapier apps for automation
  • Continuous Learning – Auto re-indexing without manual retraining
Additional Considerations
  • ⚠️ Cannot create content directly – Focuses on search/retrieval
  • Large organization focus – May be overkill for smaller teams
  • Training investment – Upskilling employees needed
  • ✅ Factual scoring – Hybrid search with reranking provides unique factual-consistency scores
  • Flexible deployment – Public cloud, VPC, or on-prem for varied compliance needs
  • Active development – Regular feature releases and integrations keep platform current
  • Time-to-value – 2-minute deployment vs weeks with DIY
  • Always current – Auto-updates to latest GPT models
  • Proven scale – 6,000+ organizations, millions of queries
  • Multi-LLM – OpenAI + Claude reduces vendor lock-in
Core Chatbot Features
  • Glean Chat interface – Natural conversations with company knowledge
  • Multi-turn conversations – Context awareness across turns
  • Streaming responses – Real-time with source citations
  • Vector + LLM search – Smart retrieval with generative answers, context-aware responses
  • Mockingbird LLM – Proprietary model with source citations (details)
  • Multi-turn conversations – Conversation history tracking for smooth back-and-forth dialogue
  • ✅ #1 accuracy – Median 5/5 in independent benchmarks, 10% lower hallucination than OpenAI
  • ✅ Source citations – Every response includes clickable links to original documents
  • ✅ 93% resolution rate – Handles queries autonomously, reducing human workload
  • ✅ 92 languages – Native multilingual support without per-language config
  • ✅ Lead capture – Built-in email collection, custom forms, real-time notifications
  • ✅ Human handoff – Escalation with full conversation context preserved
Customization & Flexibility ( Behavior & Knowledge)
  • Natural language config – Build agents without technical expertise
  • Visual builder – Drag-and-drop workflow creation
  • 30+ templates – Sales, engineering, IT, HR
  • Indexing control – Configure chunk sizes, metadata tags, retrieval parameters
  • Search weighting – Tune semantic vs lexical search balance per query
  • Domain tuning – Adjust prompt templates and relevance thresholds for specialty domains
  • Live content updates – Add/remove content with automatic re-indexing
  • System prompts – Shape agent behavior and voice through instructions
  • Multi-agent support – Different bots for different teams
  • Smart defaults – No ML expertise required for custom behavior

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Final Thoughts

Final Verdict: Glean vs Vectara

After analyzing features, pricing, performance, and user feedback, both Glean and Vectara are capable platforms that serve different market segments and use cases effectively.

When to Choose Glean

  • You value permissions-aware ai is genuinely differentiated - real-time enforcement across 100+ datasources addresses critical enterprise concern
  • Strong developer experience - comprehensive APIs, 4-language SDKs (Python, Java, Go, TypeScript), LangChain integration
  • Model flexibility without vendor lock-in - 15+ LLMs with per-step selection and bring-your-own-key option

Best For: Permissions-aware AI is genuinely differentiated - real-time enforcement across 100+ datasources addresses critical enterprise concern

When to Choose Vectara

  • You value industry-leading accuracy with minimal hallucinations
  • Never trains on customer data - ensures privacy
  • True serverless architecture - no infrastructure management

Best For: Industry-leading accuracy with minimal hallucinations

Migration & Switching Considerations

Switching between Glean and Vectara requires careful planning. Consider data export capabilities, API compatibility, and integration complexity. Both platforms offer migration support, but expect 2-4 weeks for complete transition including testing and team training.

Pricing Comparison Summary

Glean starts at $50/month, while Vectara begins at custom pricing. Total cost of ownership should factor in implementation time, training requirements, API usage fees, and ongoing support. Enterprise deployments typically see annual costs ranging from $10,000 to $500,000+ depending on scale and requirements.

Our Recommendation Process

  1. Start with a free trial - Both platforms offer trial periods to test with your actual data
  2. Define success metrics - Response accuracy, latency, user satisfaction, cost per query
  3. Test with real use cases - Don't rely on generic demos; use your production data
  4. Evaluate total cost - Factor in implementation time, training, and ongoing maintenance
  5. Check vendor stability - Review roadmap transparency, update frequency, and support quality

For most organizations, the decision between Glean and Vectara comes down to specific requirements rather than overall superiority. Evaluate both platforms with your actual data during trial periods, focusing on accuracy, latency, ease of integration, and total cost of ownership.

📚 Next Steps

Ready to make your decision? We recommend starting with a hands-on evaluation of both platforms using your specific use case and data.

  • Review: Check the detailed feature comparison table above
  • Test: Sign up for free trials and test with real queries
  • Calculate: Estimate your monthly costs based on expected usage
  • Decide: Choose the platform that best aligns with your requirements

Last updated: January 19, 2026 | This comparison is regularly reviewed and updated to reflect the latest platform capabilities, pricing, and user feedback.

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Priyansh Khodiyar's avatar

Priyansh Khodiyar

DevRel at CustomGPT.ai. Passionate about AI and its applications. Here to help you navigate the world of AI tools and make informed decisions for your business.

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