LangSmith is an observability platform designed to help teams build and ship reliable AI agents and LLM applications. It provides robust tracing capabilities to quickly debug non-deterministic LLM app behavior, allowing developers to see step-by-step what their agent is doing and fix issues to improve latency and response quality. The platform also offers live dashboards for monitoring business-critical metrics such as costs, latency, and response quality, with alerting features to notify users of issues and enable drilling down to root causes. Furthermore, LangSmith automatically discovers usage patterns and issues by clustering similar conversations, helping users understand what their users want and identify systemic problems. It integrates seamlessly with various frameworks, including LangChain and LangGraph, and supports OpenTelemetry for unified observability.

Available on: Web

Data compiled by Toolradar Pricing checked Nov 11, 2026 · How we evaluate

Source langsmith.com

Preview

Key Features

Agent tracing for step-by-step debugging of LLM applications
Live dashboards for monitoring costs, latency, and response quality
Alerts for critical business metrics
Automatic discovery and clustering of similar conversations (Insights Agent)
Support for any framework, including LangChain and LangGraph
OpenTelemetry (OTel) support for unified observability
Self-hosting option for enterprise plans
No added latency to applications

Pricing Plans

Pricing checked Nov 11, 2026. Source: langchain.com/pricing, read Nov 11, 2026

LangSmith plans and prices, checked November 2026
Plan	Price	Details
Developer	$0	$0/seat official 1 seat 5k base traces / month then pay-as-you-go
Plus	$39/month	$39/seat/month official Unlimited seats 10k base traces / month then pay-as-you-go +1 more Show less 1 free small serverless deployment
Enterprise	Custom	Quote Hybrid or self-host Custom SSO

Calculate your cost View full pricing

Is LangSmith worth the price?

Good value

LangSmith Developer is $0 for one seat and 5,000 base traces/month.

Plus is $39/seat/month with 10,000 traces and one free small serverless deploy. After the included traces you pay usage.

Seats bill on the 1st, pro-rated if added mid-month, no credit when you remove a seat. Traces bill in arrears.

They do not train on your data.

Hidden Costs & Gotchas

Traces over the included 5k/10k are pay-as-you-go. Seats are only the floor.

Base traces last 14 days. Extended traces (400 days) cost extra.

Fleet on Developer pauses after 5 LCU/month until reset or Plus.

Full LangSmith pricing: every plan, hidden costs and alternatives

How LangSmith's pricing compares

At $39/seat/mo, billed monthly, LangSmith is mid-range of its 5 comparable direct competitors ($8 to $249/mo across the set).

Datadog

Comet ML

$19

LangSmith

$39

Arize AI

$50

Weights & Biases

$60

Braintrust

$249

Not ranked, different unit or currency: Google Gemini $4.99/mo flat, whole organisation, billed monthly.

Entry paid plan, monthly price, per seat, billed monthly. Pricing checked Nov 11, 2026.

LangSmith by the numbers

Toolradar data: It is listed as an alternative to 22 other tools on Toolradar, ranking #4 of 95 in Debugging. As of Nov 2026.

LangSmith compared with 95 Debugging tools on Toolradar, as of Nov 2026
Metric	LangSmith	Peer median	Position (1 is best)
Free plan	Yes	83% have one	n/a
Listed as an alternative to	22 tools	1	#4 of 95
Compare-page visits, last 30 days	94 visits	26	#3 of 34 tools with 20+ compare-page visits

Listed as an alternative to: #4 on 2026-10-16 to #4 on 2026-11-11 (rank among 95 tools, 1 is best).

Each position is counted among the tools that have data for that row, as noted under it. All Debugging data · How we compute this. Advertising and placement fees are not inputs to any position. Visit counts include visits from every source.

Cite this: Toolradar, “LangSmith by the numbers”, Nov 2026.

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Best LangSmith Alternatives

Top alternatives based on features, pricing, and user needs.

View full list →

Google Gemini Freemium

Google's advanced AI models with multimodal understanding and deep integration

3.4

Datadog Freemium

Cloud monitoring, security, and AI investigations for DevOps

4.4

Weights & Biases Freemium

Track, compare, and share ML experiments and models

4.6

Arize AI Freemium

The AI & Agent Engineering Platform for LLM observability, evaluation, and development.

4.3

Comet ML Paid

Machine learning experiment tracking platform

4.3

OpenAI API Paid

Programmatic access to OpenAI's full model lineup: GPT-5.5, o3, gpt-image-1

3.7

Braintrust Freemium

Observability and evaluation platform for AI agents: trace production runs, score outputs with evals and build datasets from real traces.

Langfuse Freemium

Open Source LLM Engineering Platform for debugging and improving your LLM application.

See all AI agents tools →

Still deciding?

Most buyers shortlist 2 or 3 tools before committing. Pull a side-by-side comparison or browse the full alternatives shortlist below.

All LangSmith alternatives 8+ tools ranked, pricing + verdict per pick LangSmith vs Google Gemini Head-to-head: features, pricing, who wins LangSmith vs Datadog Head-to-head: features, pricing, who wins LangSmith vs Weights & Biases Head-to-head: features, pricing, who wins

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LangSmith FAQ

How does LangSmith help in debugging LLM applications?

LangSmith provides robust tracing capabilities that allow developers to debug the non-deterministic behavior of LLM applications. It enables a step-by-step view of an agent's actions, which helps in identifying and resolving issues to improve latency and response quality.

Which teams would benefit most from using LangSmith?

Teams that are building and deploying AI agents and LLM applications will find LangSmith most beneficial. It is designed for developers and operations teams who need to ensure the reliability, performance, and quality of their AI-powered products.

How is LangSmith priced?

LangSmith offers a free tier for users to get started. For more extensive usage and additional features, paid plans are available.

Can LangSmith integrate with existing observability tools?

Yes, LangSmith supports OpenTelemetry, allowing for unified observability across different systems. It also integrates seamlessly with frameworks like LangChain and LangGraph.

What kind of limitations should users be aware of with LangSmith?

One limitation is that self-hosting is exclusively available with the enterprise plan. Additionally, getting started with LangSmith requires some initial setup, such as configuring environment variables.

How does LangSmith compare to Langfuse for monitoring AI applications?

LangSmith offers comprehensive observability with robust tracing and live dashboards for debugging and monitoring LLM applications. It focuses on identifying systemic issues and user needs by clustering similar conversations, helping to understand usage patterns.

How does LangSmith assist in optimizing LLM application performance?

LangSmith helps optimize performance by providing live dashboards to monitor business-critical metrics like costs, latency, and response quality. It also includes alerting features that notify users of issues and facilitate drilling down to root causes for improvement.

Source: langsmith.com

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