# Nebius AI Cloud vs OpenAI API: who uses which

On usedby, 48 companies use Nebius AI Cloud 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: 52 of 53 public lines checked.

## Side by side

|  | [Nebius AI Cloud](https://www.usedby.ai/tools/nebius.md) | [OpenAI API](https://www.usedby.ai/tools/openai-api.md) |
|---|---|---|
| Public customers | 48 | 5 |
| Confirmed | 29 | 0 |
| Observed | 19 | 4 |
| Signals (job posts) | 0 | 1 |
| Top industries of customers (every proof level) | Artificial Intelligence (21), Biotech & Pharma (4), DevTools & Infrastructure (3) | Biotech & Pharma (1), DevTools & Infrastructure (1), Marketing Tech (1) |
| Category | AI inference & GPU cloud | Foundation models & model APIs |

## 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, Nebius AI Cloud | Proof, OpenAI API | First public proof, OpenAI API |
|---|---|---|---|
| [Cursor](https://www.usedby.ai/companies/cursor.md) | Observed | Observed | On or before October 2026 |

## Published results

Reviewed stories only; usedby did not measure the figures.

- Nebius AI Cloud: [TrialHub](https://www.usedby.ai/case-studies/trialhub-nebius.md): **50%**: “TrialHub reduces the time spent on feasibility assessments by 50%” (captured by usedby 2026-10-07)
- Nebius AI Cloud: [Krisp](https://www.usedby.ai/case-studies/krisp-nebius.md): **50–80%**: “a single H100 GPU completed the training process 50–80% faster than the A100 GPU” (captured by usedby 2026-10-07)

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