kitio.aiWeights & Biases vs Opik
A side-by-side look at pricing plans, free tiers, features, pros and cons, updated for 2026. Opik has the lower starting price: about $19 a month, against $60 for Weights & Biases.
At a glance
Best for
Category
Pricing model
Starting price
Free plan
Made by
Based in
Rating
Key features
- Experiment tracking
- Hyperparameter sweeps
- Model registry
- Weave LLM tracing
- Reports
- Tracing and spans
- Evaluation metrics
- Agent optimizer
- Guardrails
- Framework integrations
| Feature | Weights & Biases | Opik |
|---|---|---|
| Best for | Experiment tracking and LLM observability, now part of CoreWeave | Comet's open-source platform for LLM tracing and evaluation |
| Category | Models & APIs | Models & APIs |
| Pricing model | Freemium | Freemium |
| Starting price | $60/mo | $19/mo |
| Free plan | Yes | Yes |
| Made by | CoreWeave | Comet |
| Based in | United States | United States |
| Rating | No ratings yet | No ratings yet |
| Key features |
|
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Pricing compared
Opik has the lower starting price: about $19 a month, against $60 for Weights & Biases.
Free plan
Cheapest paid plan
Top plan
Free trial
3 plans
Free
Free
- Experiment tracking for individuals
- Limited storage
Pro
$60/mo
- Starting price
- Team collaboration features
- Higher usage limits
Enterprise
Contact sales
- SSO and advanced security
- Dedicated support
4 plans
Open Source
Free
- Self-hosted
- Full observability feature set
- Unlimited spans
Free Cloud
Free
- Up to 10 team members
- 25k spans per month
- 60-day data retention
Pro Cloud
$19/mo
- Up to 50 team members
- 100k spans per month
- $5 per extra 100k spans
Enterprise
Custom
- Unlimited team members
- Flexible deployments
- Single sign-on
- 2-hour response SLA
Prices in USD, checked Oct 28, 2026 or later. Plans change often, so confirm on each tool's site before you buy.
Pros and cons
Weights & Biases
- Industry-standard experiment tracking
- Polished dashboards
- Covers training and LLM apps
- Pricing jumps for larger teams
- Weave ingestion billed by size
- Sign-in moved to CoreWeave
Opik
- Free and self-hostable
- Automatic prompt optimization
- Many integrations
- Smaller community than Langfuse
- Hosted plan limits vary
- Docs split with Comet ML
Which one should you choose?
Choose Weights & Biases if you want:
- Industry-standard experiment tracking
- Polished dashboards
- Covers training and LLM apps
Watch out: pricing jumps for larger teams.
Choose Opik if you want:
- Free and self-hostable
- Automatic prompt optimization
- Many integrations
Watch out: smaller community than langfuse.
Weights & Biases vs Opik FAQ
What is the difference between Weights & Biases and Opik?
Weights & Biases: Experiment tracking and LLM observability, now part of CoreWeave. Opik: Comet's open-source platform for LLM tracing and evaluation. Both are models & apis tools.
Is Weights & Biases or Opik cheaper?
Opik has the lower starting price: about $19 a month, against $60 for Weights & Biases.
Do Weights & Biases and Opik have free plans?
Weights & Biases: Yes. Opik: Yes.
Who makes Weights & Biases?
Weights & Biases is made by CoreWeave, based in United States.
Who makes Opik?
Opik is made by Comet, based in United States.
Which should I choose, Weights & Biases or Opik?
Choose Weights & Biases if you value industry-standard experiment tracking and polished dashboards. Choose Opik if you value free and self-hostable and automatic prompt optimization.