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Glean vs Sierra: 2026 comparison

Enterprise AI worker — unified search, work assistant, and custom agents grounded in your company knowledge.

⚙️OpsAssistantSubscription
RAGMemoryTool use

Branded customer-facing agents from the founders of Salesforce + Google.

🎧SupportAutonomousSubscription
VoiceTool useMemoryRAG

Glean vs Sierra — specs

SpecGleanSierra
Agent Rank80 / 100 (A)78 / 100 (A)
AutonomyAssistantAutonomous
PricingSubscription · Free tierSubscription · Free tier
Open sourceNoNo
CapabilitiesRAG, Memory, Tool useVoice, Tool use, Memory, RAG
Integrations6 apps3 apps
VerifiedVerifiedVerified
ReleasedFeb 2025Feb 2025

Categories: GleanOps · SierraSupport

Agent Rank breakdown

Glean
Agent Rank
80/ 100
AA-tier
Autonomy fit
7
Capabilities
6
Integrations
10
Pricing value
9
Polish & maturity
6
Verifiability
10

Auto-computed from autonomy, capabilities, integrations, pricing, maturity and editorial verification. Updated every deploy. How is this computed?

Sierra
Agent Rank
78/ 100
AA-tier
Autonomy fit
9
Capabilities
8
Integrations
6
Pricing value
9
Polish & maturity
5
Verifiability
10

Auto-computed from autonomy, capabilities, integrations, pricing, maturity and editorial verification. Updated every deploy. How is this computed?

Pros & cons

Glean
Pros
  • +Single best enterprise knowledge agent in 2026 — instant grounding in your company data
  • +Custom Agents (Glean Agents) let teams build internal workflows without code
  • +Strong permission-aware retrieval — agents see only what users are allowed to
Cons
  • Enterprise-only — typically $50K+ ACV minimum
  • Initial connector setup takes weeks for full coverage
  • Pricier than ChatGPT Enterprise on a per-seat basis
Sierra
Pros
  • +Best-in-class for branded customer-facing agents (voice + chat parity)
  • +Concierge onboarding from one of the strongest teams in AI
  • +Indistinguishable-from-human quality in tier-1 deployments
Cons
  • Enterprise-only pricing — typical contracts $150–500k/year
  • Deployment is white-glove, not SaaS — multi-week setup
  • Overkill for SMB or mid-market support volumes

Pricing

Glean
Recommended
Enterprise
Custom
Enterprises 200+ employees
  • +Unified search across 100+ apps
  • +Work assistant + custom agents
  • +SSO + enterprise data isolation
Sierra
Recommended
Branded agent
Custom
Enterprise
  • +Voice + chat
  • +Custom persona
  • +White-glove implementation
  • +SOC 2 II + HIPAA option

Which one should you pick?

Glean

Pick Glean if your stack spans many tools and integration depth is the constraint.

Try Glean →
Sierra

Pick Sierra if you want the highest autonomy and the verification loop is in place.

Try Sierra →

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Frequently asked

Should I pick Glean or Sierra in 2026?+

Pick Glean if your stack spans many tools and integration depth is the constraint. Pick Sierra if you want the highest autonomy and the verification loop is in place. Most working teams running both can use Glean for primary work and Sierra for the workflows where its specific strengths matter.

What's the price difference between Glean and Sierra?+

Both Glean and Sierra start in the same pricing range (Subscription · Free tier vs Subscription · Free tier). Total cost of ownership depends on your team size and volume — see the TCO calculator for your specific math.

Which is more autonomous, Glean or Sierra?+

Sierra is the more autonomous of the two (Autonomous vs Assistant). Higher autonomy ships throughput faster but requires verification loops in place — see our autonomous-vs-copilot framing for when each tier wins.

Want the real monthly cost at your volume? Run the TCO calculator →
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