Comet vs Stability AI Pricing (2026)
How do these two stack up on price? Here's what each one costs, what you get, and where the value sits.
| Comet | Stability AI | |
|---|---|---|
| Starts at | $19/mo | Custom |
| Number of plans | 4 | 1 |
| Free plan | ||
| Free trial | ||
| Pricing model | usage-based | usage-based |
Open Source
- Full AI observability & agent testing feature set
- True OSS: same codebase as the hosted versions
- Agent tracing & analysis
- Test Suites & assertions
- Agent Playground
Free Cloud
- Up to 10 team members
- 25k spans per month
- 60-day data retention
- Agent tracing & analysis
- Test Suites & assertions
- Agent Playground
- Ollie coding harness trial
Pro Cloud
Popular- Up to 50 team members
- 100k spans per month
- 60-day data retention
- Customizable monthly span limits
- Customizable data retention periods
Enterprise
- Unlimited team members
- Custom usage plans
- Flexible deployments
- Service accounts and view-only users
- Single sign-on
- Dedicated support and SLAs
- SOC 2, ISO 27001, ISO 9001, HIPAA, and GDPR compliance
Pay-as-you-go
- Stable Image Ultra – 8 credits
- Stable Diffusion 3.5 Large – 6.5 credits
- Stable Diffusion 3.5 Large Turbo – 4 credits
- Stable Diffusion 3.5 Medium – 3.5 credits
- Stable Diffusion 3.5 Flash – 2.5 credits
- Stable Image Core – 3 credits
- SDXL 1.0 – From 0.9 credits
- Creative Upscaler – 60 credits
- Conservative Upscaler – 40 credits
- Fast Upscaler – 2 credits
- Erase Object – 5 credits
- Inpaint – 5 credits
- Outpaint – 4 credits
- Remove Background – 5 credits
- Search and Recolor – 5 credits
- Search and Replace – 5 credits
- Replace Background & Relight – 8 credits
- Structure – 5 credits
- Sketch – 5 credits
- Style Guide – 5 credits
- Style Transfer – 8 credits
- Stable Fast 3D – 10 credits
- Stable Point Aware 3D – 4 credits
- Stable Audio 2.5 – 20 credits
- Stable Audio 3.0 – 26 credits
Comet vs Stability AI FAQ
- Which one is cheaper?
- One or both use custom pricing, so it depends on your specific needs.
- Can I use either one for free?
- Both offer free plans, so you can try each without paying. Start with whichever fits your workflow better and upgrade when you hit the limits.
- How do they charge?
- Both use a usage-based model, so the comparison is straightforward — it comes down to features and limits at each price point.
- Which one is a better deal?
- Depends on what you need. Comet: At $19/mo entry, they're positioning as the accessible alternative to heavier MLOps platforms — clearly going after teams that find tools like Weights & Biases or Arize too expensive or too complex for pure LLM tracing use cases. The academic free Pro tier signals they're also playing a long game on developer mindshare. Stability AI: At a penny per credit, they're positioning as an accessible, low-barrier entry point in the generative image AI space — competing directly with Midjourney and DALL-E by removing the subscription wall and letting output volume drive cost.
Still deciding? See the best Comet alternatives or the best Stability AI alternatives, ranked with verified pricing.
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