Glean vs Nuclia

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

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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 Nuclia 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 Nuclia, 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 Nuclia if: you value specialized for unstructured data

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 Nuclia

Nuclia Landing Page Screenshot

Nuclia is ai search and rag-as-a-service for unstructured data. Nuclia is a RAG-as-a-Service platform that automatically indexes unstructured data from any source to deliver AI search, generative answers, and knowledge extraction with enterprise-grade security and multilingual support. Founded in 2019, headquartered in Barcelona, Spain, the platform has established itself as a reliable solution in the RAG space.

Overall Rating
81/100
Starting Price
$300/mo

Key Differences at a Glance

In terms of user ratings, Glean in overall satisfaction. From a cost perspective, Glean starts at a lower price point. 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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Nuclia
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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
  • Multimodal Indexing – Indexes PDF, Word, Excel, PowerPoint, web pages, images with OCR, audio/video transcription
  • Programmatic Ingestion – REST API, Python/JS SDKs, CLI for automated data uploads
  • Sync Agent – Auto-watches cloud drives and sitemaps for continuous nonstop indexing
  • Language Support – Handles virtually any text-based language (non-pictogram languages only)
  • 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
  • Model-Agnostic – OpenAI, Azure OpenAI, Google PaLM 2, Cohere, Anthropic, Hugging Face
  • 100% Private GenAI – Keep all processing on Nuclia infrastructure without third-party exposure
  • Hugging Face Integration – Drop in open-source or domain-specific models easily
  • Flexible Switching – Swap models per query to optimize cost vs quality balance
  • 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
  • Quality-Based RAG – Focused on trusted, source-linked answers with citation attribution
  • Hybrid Search – Tune semantic vs keyword weighting for domain precision
  • Entity Enrichment – Summaries and entity extraction improve Q&A quality
  • Large-Scale Ready – Scales to large datasets; speed depends on LLM choice
  • 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
  • Rich APIs – REST APIs, Python/JS SDKs, CLI for ingestion and querying
  • Modular Design – Index first, query later workflow fits dev processes
  • Self-Host Option – On-prem NucliaDB for complete infrastructure control
  • Open-Source – NucliaDB GitHub (710+ stars, AGPLv3) with transparent code
  • 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
  • No-Code Widget – Drop search/Q&A panel onto websites in minutes
  • Workflow Automation – n8n and Zapier integration for thousands of service connections
  • API-First Design – Embed into any channel via REST API/SDKs
  • ⚠️ No Native Bots – No one-click Slack/Teams bots (requires custom development)
  • 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
  • Widget Styling – No-code widget offers basic styling customization options
  • Custom Prompts – Set system prompts to adjust tone and response style
  • Custom UI – Build fully branded front-end on flexible API
  • ⚠️ Advanced Branding – Deep customization requires developer resources and API integration
  • 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
  • Usage Dashboard – Track token spend for indexing and query operations
  • Activity Logs – Audit trails for ingestion and query events
  • API/CLI Access – Send logs to Splunk, Elastic, or monitoring tools
  • ⚠️ Custom Analytics – Conversation analytics require custom front-end implementation
  • 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
  • Consumption Model – Base license plus usage costs (indexing, queries, LLM calls)
  • Granular Control – Light usage stays cheap, scales automatically for heavy use
  • Free Trial – Hands-on evaluation before committing to paid plans
  • On-Prem Economics – Self-hosting provides cost control with existing infrastructure
  • 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
  • GDPR Compliant – EU-based with strict data protection; no cross-customer training
  • Data Isolation – Knowledge Boxes with disk encryption and tenant separation
  • On-Prem Deployment – Self-host NucliaDB for complete data residency and control
  • Enterprise SSO – Role-based access with regional data centers (EU available)
  • 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
  • No-Code Dashboard – Create Knowledge Box → upload data → tune → embed widget
  • Defaults Work – Out-of-box settings are production-ready for basic use
  • ⚠️ Technical Sliders – Advanced retrieval/prompt options may confuse non-technical users
  • ⚠️ Custom UI Needed – Full branding requires building on API front-end
  • 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
  • Documentation – Comprehensive docs, API reference, code samples, quick-start guides
  • Community – Slack community, Stack Overflow, developer forums for peer support
  • LangChain Integration – Official integration with popular AI frameworks
  • Enterprise Support – Dedicated assistance for on-prem/hybrid installations
  • 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 RAG-AS-A-SERVICE with managed infrastructure and API-first design
  • Agentic Focus – Progress Agentic RAG with autonomous decision-making capabilities
  • Fully Managed – Hosted NucliaDB with auto-scaling, chunking, embedding, no infrastructure management
  • Model-Agnostic Service – Switch LLM providers without architectural changes (OpenAI, Azure, PaLM, Anthropic)
  • Agent-Ready – Only RAG platform designed for AI agents (CrewAI, LangChain compatible)
  • Hybrid Deployment – Cloud-managed with on-prem NucliaDB for data sovereignty
  • 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 – API-first RAG platform with multimodal indexing and model-agnostic architecture
  • Target Customers – Dev teams needing text/audio/video search with on-prem/hybrid deployment options
  • Key Competitors – Deepset/Haystack, Vectara.ai, Azure AI Search, custom RAG implementations
  • Competitive Advantages – Multimodal OCR/speech-to-text, 100% private GenAI, open-source NucliaDB portability
  • Pricing Advantage – Consumption model controls costs; light usage cheap, enterprise-ready scalability
  • 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
  • Model-Agnostic – OpenAI, Azure OpenAI, PaLM 2, Cohere, Anthropic, Hugging Face
  • Private GenAI – 100% Nuclia-hosted infrastructure option for data isolation
  • Flexible Switching – Swap models per query without architectural changes
  • Local Models – Self-hosted models supported (requires extra setup)
  • ✅ Developer Freedom – Choose optimal LLM per Knowledge Box or query
  • 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
  • Quality-Based RAG – Trusted answers with comprehensive source citations for transparency
  • Hybrid Search – Combine semantic vectors with keyword matching for precision
  • Customizable Chunking – Adjust chunk sizes, weighting, segmentation for context windows
  • Knowledge Graph – Auto entity/relationship extraction enriches corpus for Q&A
  • Multimodal Indexing – OCR for images, speech-to-text creates comprehensive knowledge base
  • ✅ Open Architecture – NucliaDB open-source provides transparency vs black-box competitors
  • 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
  • Enterprise Search – Modernize legacy search with AI across text/audio/video
  • Customer Support – Internal Q&A for support teams from product documentation
  • Multimodal Discovery – Unified search across PDFs, videos, audio, presentations
  • Regulatory Compliance – GDPR-compliant retrieval with data residency guarantees
  • Developer RAG Backend – API-first infrastructure for custom AI applications
  • 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
  • GDPR Compliant – EU-based; customer data never used for model training
  • Data Isolation – Knowledge Boxes with disk encryption; zero cross-training
  • On-Prem Options – Self-host NucliaDB and local LLMs for data sovereignty
  • Enterprise SSO – Identity provider integration with role-based access control
  • Regional Centers – EU and other regions for local data residency laws
  • 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
  • Pricing Model – License plus consumption (base plus indexing/queries/LLM calls)
  • Free Trial – Available for hands-on evaluation before commitment
  • Granular Control – Pay for usage; light stays cheap, scales automatically
  • Transparent Billing – Storage, indexing, queries, LLM usage clearly itemized
  • Best Value For – Organizations optimizing costs through usage control vs seat-based pricing
  • 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
  • Comprehensive Docs – docs.nuclia.dev with guides, API reference, code examples
  • Active Community – Slack community, Stack Overflow, developer forums
  • Open-Source – NucliaDB GitHub (710+ stars, AGPLv3) with transparent code
  • LangChain Integration – Official integration for AI framework ecosystem compatibility
  • Enterprise Support – Dedicated support for on-prem/hybrid installations
  • 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
  • ⚠️ API-First Complexity – Developer-focused; not plug-and-play for non-technical teams
  • ⚠️ No Turnkey UI – Advanced branding requires building custom front-end
  • ⚠️ No Native Bots – Slack/Teams bots require custom API development
  • ⚠️ Language Limits – Cannot index pictogram-based languages (Japanese, Chinese characters)
  • ⚠️ Learning Curve – Advanced RAG parameters feel technical for beginners
  • ✅ Best For Developers – Capable platform for technical teams with resources
  • 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 – Autonomous decision-making for retrieval strategies vs manual configuration
  • CrewAI Integration – Official integration for orchestrating autonomous AI agent teams
  • AI Search Copilot – Customizable LLM agents for employee support and customer service
  • Ingestion Agents (Beta) – Auto-labeling, summarization, graph extraction, Q&A generation, content safety
  • ⚠️ Missing Features – No lead capture, human handoff, proactive alerting workflows
  • 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
  • ✅ Beyond Search – AI search, Q&A, classification, multi-language multimodal indexing
  • ✅ Enterprise RAG – Replace legacy search across text, audio, video content
  • ✅ Open-Source Core – Reduces lock-in, enables extension and self-hosting
  • ⚠️ DevOps Effort – Advanced setups need ML/DevOps resources for deployment
  • 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
  • AI Search + Q&A – Semantic search with generative answers from your data
  • Source Citations – Shows exact sources for answer transparency and trust
  • Auto-Summarization – Summarizes long docs with entity recognition and AI classification
  • Multi-Turn Chat – Handles one-shot Q&A and conversational multi-turn interactions
  • ✅ #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
  • Retrieval Tuning – Adjust chunk sizes, weighting, metadata filters for precision
  • Per-Query Prompts – Custom prompts per query for dynamic persona/style
  • Knowledge Boxes – Multiple isolated data spaces with tags for scope
  • Structured Output – Return JSON or fine-tune private models for specific needs
  • 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 Nuclia

After analyzing features, pricing, performance, and user feedback, both Glean and Nuclia 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 Nuclia

  • You value specialized for unstructured data
  • Strong multilingual support (100+ languages)
  • SOC2 Type 2 and ISO 27001 compliant

Best For: Specialized for unstructured data

Migration & Switching Considerations

Switching between Glean and Nuclia 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 Nuclia begins at $300/month. 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 Nuclia 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: February 17, 2026 | This comparison is regularly reviewed and updated to reflect the latest platform capabilities, pricing, and user feedback.

See Also

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The most accurate RAG-as-a-Service API. Deliver production-ready reliable RAG applications faster. Benchmarked #1 in accuracy and hallucinations for fully managed RAG-as-a-Service API.

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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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