Suggestions appear as you type. Use the up and down arrows to choose one and Enter to open it.

This page's audience our own tag's counts — open to see them
–Visits
–Page views
–Clicks to vendors
–Time on page
–Reading now
Clicks to vendors, by tool
  • –
Top countries
  • –
Devices
  • –

– · visits, page views and clicks counted by our own tag, which counts more than our checked analytics; every figure rounded down · how we count

Head-to-head · AI LLM Evaluation Tools

Promptfoo vs LangSmith

  • Updated Oct 2026
  • Both researched from official sources
  • 1 check side by side
Higher score Promptfoo #3 in AI LLM Evaluation Tools 9.2/10 Free plan Free plan✓ 0 of 3 features Visit Promptfoo
LangSmith #4 in AI LLM Evaluation Tools 9.1/10 Free plan Free plan✓ 0 of 3 features Visit LangSmith

Promptfoo leads on 0 checks, LangSmith on 0, and 1 is even. Who comes out ahead on the 1 yes/no, price and count check where we have data for both products. The editor score weighs everything else too.

Our verdict

  • Highest scorePromptfoo · 9.2/10
  • Free planboth

Promptfoo scores higher on our rubric for ai llm evaluation tools: 9.2 against 9.1 out of 10; our editors rank them #3 and #4.

Promptfoo is the better fit for teams prioritizing testing and red teaming. LangSmith is the better fit for langChain-based teams needing a mature platform.

  • Promptfoo fits best

    Teams prioritizing testing and red teaming

  • LangSmith fits best

    LangChain-based teams needing a mature platform

Advertiser disclosure: iTechGuides is reader-supported. Vendors can pay for top positions in our rankings and for a place on other products' pages, and we may earn a commission when you click some links. Bought places stand at the number bought; this page and our disclosure say so. Paying vendors may get a fuller, more detailed review from our editors, and that review can change their score. How we rank.

Side by side

Feature Promptfoo 9.2/10 Visit ↗ LangSmith 9.1/10 Visit ↗
At a glance
Editor score 9.2 9.1
Ranking #3 in AI LLM Evaluation Tools #4 in AI LLM Evaluation Tools
Best for Teams prioritizing testing and red teaming LangChain-based teams needing a mature platform
Pricing model Free plan + paid Free plan + paid
Starting price — $39/seat/mo
Free plan ✓ ✓
Free trial — —
Deployment Cloud, Self-hosted Cloud, Self-hosted
Platforms Web Web
Support Community, Docs Community, Email, Tickets, Docs · 24/7
Compliance SOC 2, ISO 27001 SOC 2, ISO 27001, GDPR, HIPAA, SSO/SAML
Integrations 12 integrations 7 integrations
Built for Solo, Small business, Mid-market, Enterprise Solo, Small business, Mid-market, Enterprise
Features Promptfoo 0/3 · LangSmith 0/3
Safety evaluations Not checked yet Not checked yet
Prompt versioning Not checked yet Not checked yet
API access Not checked yet Not checked yet
Specs
Evaluation methods Not checked yet Not checked yet
Model support Not checked yet Not checked yet
Deployment Not checked yet Not checked yet
Our review
Pros
  • Evaluates prompts, models, RAG pipelines, safety, and vulnerabilities
  • Supports custom metrics, human review, and LLM-as-a-judge grading
  • Connects with major providers, CI tools, observability, and MCP
  • Tracing, evaluations, prompt versioning, datasets, and monitoring in one platform
  • Supports LangChain, LangGraph, major model providers, and OpenTelemetry
  • Cloud, hybrid, and self-hosted deployment options
Cons
  • Enterprise and On-Premise plans use custom pricing
  • Team collaboration and continuous monitoring require Enterprise
  • Dedicated deployment engineering is limited to On-Premise
  • Usage-based charges apply after included trace allowances
  • Enterprise pricing is custom rather than publicly listed
  • The Developer plan is limited to one seat
Our verdict

Promptfoo is an open-source CLI and library for evaluating, testing, and red-teaming large-language-model applications. It is designed for teams benchmarking prompts, models, and RAG pipelines, as well as developers checking AI quality,…

Read the review →

LangSmith is a commercial platform from LangChain Inc. for developing, testing, monitoring, evaluating, and deploying LLM applications and agents. It is designed for LangChain- and LangGraph-based teams, while also supporting applications…

Read the review →
  1. PromptfooAI LLM Evaluation Tools 9.2Free plan
  2. LangSmithAI LLM Evaluation Tools 9.1Free plan

Strengths and trade-offs

  • Promptfoo — where it wins

    • Evaluates prompts, models, RAG pipelines, safety, and vulnerabilities
    • Supports custom metrics, human review, and LLM-as-a-judge grading
    • Connects with major providers, CI tools, observability, and MCP

    Where it doesn't

    • Enterprise and On-Premise plans use custom pricing
    • Team collaboration and continuous monitoring require Enterprise
    • Dedicated deployment engineering is limited to On-Premise

  • LangSmith — where it wins

    • Tracing, evaluations, prompt versioning, datasets, and monitoring in one platform
    • Supports LangChain, LangGraph, major model providers, and OpenTelemetry
    • Cloud, hybrid, and self-hosted deployment options

    Where it doesn't

    • Usage-based charges apply after included trace allowances
    • Enterprise pricing is custom rather than publicly listed
    • The Developer plan is limited to one seat

More comparisons

All AI LLM evaluation tools comparisons → · Full ranking →

Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026

Last updated · How we research and update