# Baseten vs OpenAI API: who uses which

On usedby, 49 companies use Baseten and 5 use OpenAI API. 1 company uses both, including Cursor. Counts include every proof level, job-post signals included; each company keeps its proof level on each side. Latest check 2026-10-14: 53 of 54 public lines checked.

## Side by side

|  | [Baseten](https://www.usedby.ai/tools/baseten.md) | [OpenAI API](https://www.usedby.ai/tools/openai-api.md) |
|---|---|---|
| Public customers | 49 | 5 |
| Confirmed | 21 | 0 |
| Observed | 28 | 4 |
| Signals (job posts) | 0 | 1 |
| Top industries of customers (every proof level) | Artificial Intelligence (19), DevTools & Infrastructure (10), HealthTech & Digital Health (6) | Biotech & Pharma (1), DevTools & Infrastructure (1), Marketing Tech (1) |
| Category | AI inference & GPU cloud | Foundation models & model APIs |
| Your data | Not used to train models by default. ([baseten.co](https://www.baseten.co/dpa/#baseten-data-processing-addendum), checked 2026-10-06) | — |
| Data processing terms | A data processing agreement is available. ([trust.baseten.co](https://trust.baseten.co/), checked 2026-10-06) | — |

## Companies that use both

Every proof level counts; the proof level of each side is shown, strongest proofs first. The first public proof is not an adoption date.

| Company | Proof, Baseten | Proof, OpenAI API | First public proof, Baseten | First public proof, OpenAI API |
|---|---|---|---|---|
| [Cursor](https://www.usedby.ai/companies/cursor.md) | Observed | Observed | On or before December 2025 | On or before October 2026 |

## Published results

Reviewed stories only; usedby did not measure the figures.

- Baseten: [Magicare.ai](https://www.usedby.ai/case-studies/magicare-ai-baseten.md): **33%**: “33% reduction in cost” (published 2026-10-11)
- Baseten: [OpenEvidence](https://www.usedby.ai/case-studies/openevidence-baseten-2.md): **$1.9M**: “is projected to save us $1.9M” (published 2026-02-20)

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Source: https://www.usedby.ai/compare/baseten-vs-openai-api · How we check: https://www.usedby.ai/methodology