Machine Learning · head to head
Comet ML vs Langfuse
Comet ML
Machine Learning
Platform for tracking, comparing, and optimizing ML experiments
- From
- Free
- Rated
- -
Langfuse
Software Development
Simple pricing for projects of all sizes
- From
- Free
- Rated
- -
The short version
- Each has a real cost: Comet ML the free cloud tier caps data at 25,000 spans a month with 60 day retention; Langfuse free Hobby plan limited to 2 users and 30-day data retention
Where they differ
Only the attributes on which Comet ML and Langfuse actually diverge.
Identical on both: starting price (Free), pricing model (freemium), free tier (Yes), user rating (Not yet rated).
What each one covers
Drawn from each product's published feature list. An absence here means we hold no record of it - not that the product lacks it.
Only in Comet ML
- Experiment tracking
- Code versioning
- Model registry
- Hyperparameter optimization
- Production monitoring
- PyTorch
- TensorFlow
- Keras
Only in Langfuse
Nothing recorded that Comet ML does not also cover.
What people use each for
The jobs each tool is most often brought in to do.
Comet ML
- LLM observability and monitoringnot Langfuse
- AI agent testing and debuggingnot Langfuse
- Experiment tracking for machine learningnot Langfuse
- Model registry and version managementnot Langfuse
- ML model training monitoringnot Langfuse
Langfuse
No use cases recorded yet. See the Langfuse review.
Where each one falls short
Documented limitations, not opinions. Every one is a constraint you would hit in normal use.
Comet ML
- The free cloud tier caps data at 25,000 spans a month with 60 day retention
- Retention stays at 60 days even on the paid Pro plan, and extending it is a $29 per 100k spans add on
- Overage on Pro is $5 per additional 100,000 spans
- The free MLOps tier is a single user with 100 GB of storage and training hours governed by a fair usage policy
- Pro MLOps is $19 per user per month and caps the team at 10 users
Langfuse
- Free Hobby plan limited to 2 users and 30-day data retention
- Overage pricing applies beyond included units; graduated rates from $8.00 per 100k units down to $6.00 per 100k units at 50M+ volume
Pricing, plan by plan
Comet ML
Free- Free CloudFree
- Up to 10 team members
- 25,000 spans per month
- 60-day data retention
- Pro Cloud$19/month
- Up to 50 team members
- 100,000 spans per month
- 60-day data retention
- MLOps FreeFree
- 1 user with fair usage policy
- Experiment tracking
- Dataset management
- MLOps Pro$19/user/month
- Up to 10 users
- 1,500 training hours included
- 500GB storage included
Langfuse
Free- HobbyFree
- 50k units/month
- 30-day data retention
- 2 users maximum
- Core$29/month
- 100k units/month
- 90-day data retention
- Unlimited users
- Pro$199/month
- 100k units/month
- 3-year data retention
- SOC2 & ISO27001 compliance
- Enterprise$2499/month
- Custom rate limits
- Dedicated support engineer
- SCIM API & audit logs
Which should you pick?
Choose Comet ML if
- You need experiment tracking.
- You want to start without paying.
- You work on Web, Linux, Mac, Windows.
- You also want code versioning.
Questions people ask
- Is Comet ML or Langfuse better?
- Neither clearly leads. Comet ML starts at Free and Langfuse at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
- Which is cheaper, Comet ML or Langfuse?
- Comet ML starts at Free and Langfuse at Free.
- Does Comet ML or Langfuse run on more platforms?
- Comet ML runs on Web, Linux, Mac, Windows. Langfuse runs on Web.
- Can I use Comet ML for free?
- Both have a free tier, so you can try either at no cost before committing.
- What is Comet ML best used for?
- Comet ML is most often used for llm observability and monitoring, ai agent testing and debugging, experiment tracking for machine learning, model registry and version management. Of those, llm observability and monitoring and ai agent testing and debugging are not what Langfuse is typically brought in for.
- What can Comet ML do that Langfuse cannot?
- Comet ML covers Experiment tracking, Code versioning, Model registry, Hyperparameter optimization.
Answered from the vendors’ own pages
Comet ML: Does Comet.ml offer a free plan?
Yes, Comet.ml offers free tiers for both Opik (cloud observability) and MLOps platforms. Free Cloud Opik includes up to 10 team members and 25,000 spans/month. Free MLOps tier is limited to 1 user.
SourceLangfuse: What does Langfuse cost?
Langfuse starts at $29/month for the Core plan (100k units/month). Pro costs $199/month with 3-year data retention. Enterprise costs $2499/month for custom rate limits and dedicated support.
SourceComet ML: How many team members can use the free Comet.ml tier?
Free Cloud supports up to 10 team members. The Pro Cloud plan supports up to 50 team members at $19/month.
SourceLangfuse: Does Langfuse have a free plan?
Yes, the Hobby plan is free with 50k units/month, 30-day data retention, and support for up to 2 users.
SourceComet ML: What is a span in Comet.ml pricing?
A span represents a single tracked operation such as model requests or function calls. Free Cloud tier includes 25,000 spans per month.
SourceLangfuse: What happens if I exceed my unit limits on Langfuse?
Overage pricing applies with graduated rates: $8.00 per 100k units for 100k-1M units, $7.00 per 100k units for 1M-10M units, $6.50 per 100k units for 10M-50M units, and $6.00 per 100k units for 50M+ units.
SourceComet ML: Does Comet.ml offer academic pricing?
Yes, a free Pro plan is available for academic users; verification is required via signup.
SourceLangfuse: Are there discounts available on Langfuse?
Early-stage startups receive 50% off the first year. Research and student accounts qualify for up to 100% off. Non-profits receive $199 monthly credits.
SourceRelated pages
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- Langfuse vs DataRobot
- Langfuse vs MLflow
- Langfuse vs Snowflake
- Langfuse vs TensorFlow
- Langfuse vs Jupyter
- Langfuse vs LangChain
- Langfuse vs Pinecone
- Langfuse vs Python
- Langfuse vs PyTorch
- Langfuse vs scikit-learn
- Langfuse vs Apache Spark MLlib
- Langfuse vs Weaviate
- Langfuse vs Weights & Biases
- Langfuse vs Alteryx
- Langfuse vs Anaconda
- Langfuse vs Cursor
- Langfuse vs Windsurf
- Langfuse vs Zed
- Langfuse vs Amp
- Langfuse vs Braintrust
- Langfuse vs Codacy
- Langfuse vs DeepSource
- Langfuse vs Devin
- Langfuse vs SonarQube Cloud
- Langfuse vs Augment Code
- Langfuse vs Baseten
- Langfuse vs Drizzle ORM
- Langfuse vs Flagsmith
- Langfuse vs Unleash
- Langfuse vs Bun
- Langfuse vs Cline
- Langfuse vs Factory
- Langfuse vs Humanloop