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Comparison

Logfire vs Langfuse

Logfire brings LLM tracing and evaluation into full-stack observability, with PostgreSQL-compatible SQL across the surrounding application, infrastructure, traces, logs, and metrics.

Feature comparison

Quick comparison

Logfire and Langfuse compared feature by feature
Feature Logfire Langfuse
Observability scope AI and application telemetry across traces, logs, and metrics LLM tracing, prompts, evaluation, and datasets
LLM Tracing Yes Yes
Token/Cost Tracking Yes Yes
Prompt Playground Yes Yes
Human annotations & queues Annotations on production runs + annotation queues Annotations on production runs + annotation queues
Hosted evaluation LLM judges and deterministic evaluators on live traffic Model-based and custom evaluators
Continuous improvement Scheduled proposals and model-swap recommendations Evaluation and prompt workflows
Full-stack workflow Traces, logs, metrics, and infrastructure views Trace-oriented LLM observability
Database/API context Native OTel integrations and service context Can ingest arbitrary OTel spans within traces
Query Interface PostgreSQL-compatible SQL Product UI, metrics API, and public API
MCP server SQL queries over production telemetry from your editor or AI agent Query observations, metrics, scores, datasets, and annotation queues
OpenTelemetry Native across full-stack telemetry Native OTLP trace ingestion
Self-Hosting Enterprise Open Source
Free Tier 10M logs, spans, and metrics 50K units
Python SDK Native OpenTelemetry SDK Native OpenTelemetry SDK
JavaScript SDK Native OpenTelemetry SDK Native OpenTelemetry SDK
Any OTel Language Yes Yes
Pricing

How each product meters usage

Logfire and Langfuse cloud pricing models
Pricing dimension Logfire Langfuse
Usage meter Logs + spans + metrics Traces + observations + scores
Free cloud allowance 10M records/month 50K units/month
Paid cloud base $49/month Team $29/month Core
List-price overage $2/million records Starts at $8/100K units; volume discounts
See the exact pricing math and sources 7 published inputs · 2 official sources · checked August 19, 2026

Calculation scope

Published cloud meters and one vendor-calculator example. No cross-vendor total is claimed because a Langfuse trace, observation, and score each count as units while Logfire meters telemetry records.

Basis: USD; public monthly list price. Prices checked .

Published inputs

Logfire Team base
$49/month Pydantic Logfire source
Logfire included telemetry
10,000,000 records/month Pydantic Logfire source
Logfire additional telemetry
$2 per 1,000,000 records Pydantic Logfire source
Langfuse Hobby allowance
50,000 units/month Langfuse source
Langfuse Core base
$29/month Langfuse source
Langfuse Core allowance
100,000 units/month Langfuse source
Langfuse usage from 100,000 to 1,000,000 units
$8 per 100,000 units Langfuse source

Assumptions

Equivalent total
Not calculated The products' units are not one-to-one without specifying the number of observations and scores per trace.

Calculations

Langfuse's own 200,000-unit Core example

This reproduces the default values displayed by Langfuse's official pricing calculator.

Langfuse
$37
  1. Core base $29 $29
  2. Additional units (200K − 100K included) ÷ 100K × $8 $8

Source ledger

  1. Pydantic Logfire — Pricing and plans for Pydantic Logfire Official vendor source · checked https://pydantic.dev/pricing
    “Covers 10 million logs, spans, and metrics every month.”

    The official calculator shows 20 million records and no extra seats totaling $69/month on Team.

  2. Langfuse — Langfuse pricing and calculator Official vendor source · checked https://langfuse.com/pricing?calculatorOpen=true
    “100k units / month included, additional: $8/100k units.”

    The official calculator shows a $37 Core total at 200,000 monthly units: $29 base plus $8 usage.

What this calculation does not include

  • Langfuse applies lower graduated rates above one million units; the visible table deliberately says the overage starts at $8 per 100,000.
  • Provider and model charges are excluded from both products.
Key differences

Why teams choose Logfire

Full-stack scope

Agent behavior depends on the application around it. Logfire makes model calls, tools, browser RUM and session replay, database queries, APIs, services, logs, metrics, and infrastructure available in the same product, instead of centering the investigation on LLM observations alone.

OpenTelemetry across the whole stack

Logfire applies OpenTelemetry across the entire application, including model and tool calls, databases, APIs, services, logs, metrics, and infrastructure. That keeps instrumentation portable while preserving the context needed to explain production behavior.

SQL query interface

Query telemetry with PostgreSQL-compatible SQL, including joins, aggregations, and ad hoc questions that were not anticipated by a saved dashboard. The same interface is available to coding agents through Logfire's MCP server.

Improve from production evidence

Run hosted LLM judges and deterministic evaluators on sampled production traffic, route low-scoring runs to human review, and turn the resulting evidence into scheduled optimization proposals and model-swap recommendations.

Decision guide

Which should you choose?

Choose Logfire if

  • You want agent traces connected to the surrounding application and infrastructure
  • You want PostgreSQL-compatible SQL and MCP over production telemetry
  • You want hosted evals, human review, and optimization connected to production traces
  • You want one OpenTelemetry-native workflow across languages and frameworks

Choose Langfuse if

  • Your team is already standardized on Langfuse and wants to keep its existing LLM workflow
FAQ

Common questions

What is the main difference between Logfire and Langfuse?

Logfire puts LLM tracing, prompts, evaluation, and optimization inside full-stack observability, so model and tool calls stay connected to browser RUM and session replay, databases, APIs, services, logs, metrics, and infrastructure.

Is Logfire more expensive than Langfuse?

The meters are different. Logfire includes 10 million records a month on its free plan; paid plans start at $49 a month and charge $2 per million additional records. Langfuse includes 50,000 units on Hobby or 100,000 on Core, then applies graduated per-unit pricing. In Langfuse, traces, observations, and scores each count as units.

Can I use Logfire with LangChain?

Yes. Logfire provides auto-instrumentation for LangChain, LlamaIndex, OpenAI, Anthropic, and many other AI frameworks. You can visualize complex chains and retrieval flows automatically.

Can I migrate from Langfuse to Logfire?

Yes. Logfire accepts standard OpenTelemetry traces, so you can send the same telemetry to Logfire while you compare production investigations and move integrations incrementally.

Can I self-host Logfire?

Yes. Logfire is available as a managed cloud service or as an Enterprise self-hosted deployment, and its SDK is open source.

Can Logfire evaluate live traffic?

Yes. Run hosted LLM judges or deterministic evaluators without supplying a model key, sample live production traffic, and route low-scoring runs to a human annotation queue. Scores become telemetry you can query, dashboard, and alert on.

Ready to switch from Langfuse?

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