Comet ML
ML experiment tracking and model monitoring, plus the open-source Opik LLM evaluator.
why this verdict
Downgrade — pay for the workflow, not the AI
Weights & Biases and MLflow cover the headline feature free, so the $50/mo is now paying for the workflow around it.
- A named launch, not a vibe named, unlinked
- Weights & Biases dominating experiment tracking while LLM observability crowds the new lane. OpenAI, August 5, 2025 — no announcement link recorded yet.
- How much of the job it covers headline only editorial call
- The headline feature, but not the workflow, data or integrations around it.
- Is there a free way to do it? yes
- 3 of 3 listed replacements have a usable free tier: Weights & Biases, MLflow and Langfuse.
- What the call is worth $600/yr
- $50/mo at the entry paid tier — $600 a year per seat.
- Threatened by
- OpenAI
- Since
- August 5, 2025
- List price
- $50/mo
- Per year
- $600
The backstory
Comet does experiment tracking, model registry and production monitoring, and open-sourced Opik for LLM tracing and evaluation, which is genuinely good and free. Its problem is being second in a category with a strong leader while the growth has moved to LLM observability, where a dozen well-funded startups arrived at once. Opik was a smart move that earned real adoption, but Comet is now competing on two fronts against different opponents.
Escape hatches
switching could free up $600/yrThe category leader with the largest community
wandb.ai open_in_newFree and open-source, no vendor at all
mlflow.org open_in_newBetter focused if you only need LLM observability
langfuse.com open_in_new3 of 3 replacements have a usable free tier.
