ChatGPT-4o (March 2025) is cheaper than Claude Opus 4 at $5/M vs $15/M input tokens.
| Spec | ChatGPT-4o (March 2025) | Claude Opus 4 |
|---|---|---|
| Input price | $5/M tokens | $15/M tokens |
| Output price | $15/M tokens | $75/M tokens |
| Context window | 128K tokens | 200K tokens |
| Parameters | Not disclosed | Not disclosed |
| Weights | — | Closed |
| Free API (OpenRouter) | No | No |
| Released | Mar 2025 | May 2025 |
Not enough votes to call it. On the specs, Claude Opus 4 has the edge: newer, bigger context window.
ChatGPT-4o (March 2025) costs 5.0x less per token.
ChatGPT-4o (March 2025) is cheaper on both: 3.0× input, 5.0× output.
No hosts listed on OpenRouter.
Per million tokens. Prices and uptime via OpenRouter, checked 9 Sep 2026.
Claude Opus 4 uses 4.5x more transitions