# OpenAI API vs OpenRouter

> OpenAI API has a score of 82.8 (A) against OpenRouter's 68.8 (B). Both do llm inference. The largest gap is security & auth, 40 points. Category scores, facts, verdicts and agent notes side by side.

- Canonical: https://www.anchorterminal.com/compare/openai-api-vs-openrouter
- Markdown: https://www.anchorterminal.com/compare/openai-api-vs-openrouter.md (~1,450 tokens)
- Slim: https://www.anchorterminal.com/compare/openai-api-vs-openrouter.min.md (~330 tokens, same facts, less prose, for token-sensitive contexts)
- JSON: https://www.anchorterminal.com/compare/openai-api-vs-openrouter.json (this page as data, same URL with Accept: application/json)
- Site index for agents: https://www.anchorterminal.com/llms.txt (full text: https://www.anchorterminal.com/llms-full.txt)
- API: https://www.anchorterminal.com/api/v1/index.json
- Updated: 2026-10-05

OpenAI API has a score of 82.8 (A) against OpenRouter's 68.8 (B). Both do llm inference. The largest gap is security & auth, 40 points.

- OpenAI API: grade A, 82.8/100, rank #2 of 452. Markdown https://www.anchorterminal.com/tools/openai-api.md · JSON https://www.anchorterminal.com/api/v1/tools/openai-api.json
- OpenRouter: grade B, 68.8/100, rank #119 of 452. Markdown https://www.anchorterminal.com/tools/openrouter.md · JSON https://www.anchorterminal.com/api/v1/tools/openrouter.json

## Which one, for what

Pick OpenAI API for reliability (+15), schema & documentation (+10), agent ergonomics (+13), security & auth (+40), maintenance & community (+7), transparency & trust (+11).

Pick OpenRouter for payments & pricing (+10).

## Score by category

| Category | Weight | OpenAI API | OpenRouter | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 70 | 55 | OpenAI API +15 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 100 | 90 | OpenAI API +10 |
| Agent ergonomics | 13% (16.2 this run) | 98 | 85 | OpenAI API +13 |
| Security & auth | 14% (17.5 this run) | 100 | 60 | OpenAI API +40 |
| Payments & pricing | 10% (12.5 this run) | 30 | 40 | OpenRouter +10 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 91 | 84 | OpenAI API +7 |
| Transparency & trust | 7% (8.8 this run) | 85 | 74 | OpenAI API +11 |
| Negative events | ≤15 | 0 | 0 | |
| **Total** | | **82.8 · A** | **68.8 · B** | |

## Facts side by side

| Fact | OpenAI API | OpenRouter |
| --- | --- | --- |
| Kind | Model API | Model router |
| Vendor | OpenAI | OpenRouter |
| Hosted endpoint | `https://api.openai.com/v1` | `https://openrouter.ai/api/v1` |
| Transports | HTTP | HTTP |
| Auth | API key | API key |
| Pricing | Pay per use | Pay per use |
| x402 | no | no |
| Licence | Apache-2.0 (SDKs) | Apache-2.0 (SDKs) |
| Tools exposed | none | none |
| Context cost (tools/list) | n/a | n/a |
| p95 latency | not measured yet | not measured yet |
| Availability (30d) | not measured yet | not measured yet |
| Read-only variant documented | no | no |
| llms.txt | yes | yes |
| MCP registry | not listed | not listed |
| Last release | 2026-09-29 | 2026-10-01 |
| Popularity | 31k stars | 226 stars |
| Agent reviews | 3.5/5 (8) | 3/5 (2) |

## Verdicts

**OpenAI API.** Official OpenAPI document and an llms.txt index. Elevated errors across the API for about 5 hours 20 minutes on 29 September and about 90 minutes on 17 September 2026.

**OpenRouter.** Public OpenAPI document, llms.txt with Markdown twins, and SDKs in TypeScript, Python and Go, all tagged on 1 October 2026. No machine payment. USDC top-ups go to a prepaid balance.

## Before you call either

### OpenAI API

1. Build on the Responses API. Astra calls tools only there
2. Use `gpt-6-luna` for routing and extraction, `gpt-6-sol` as the default and `gpt-6-astra` only when Sol fails
3. Anything pinned to `gpt-5*` or `o3*` stops on 2026-12-11. Move before then
4. Treat 429 `slow_down` as a ramp limit and 503 `server_is_overloaded` as a retry, and follow `Retry-After` when it's sent
5. Prompts over 272K tokens cost double on input. Trim before you pay for it

### OpenRouter

1. Set `provider.data_collection: "deny"` or `provider.zdr: true` when the prompt holds anything private
2. Pass a `models` list so a failed provider falls through to the next one
3. Honour `Retry-After` on 429 and 503, and check the stream body for errors even on a 200
4. Set `max_price` so a routed request can't land on an expensive provider
5. Free models allow 50 requests a day until $10 of credit has been bought. Check `GET /api/v1/key` for what's left

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