Claude Sonnet 4 is cheaper than GPT-6 Astra Pro at $3/M vs $10/M input tokens.
| Spec | Claude Sonnet 4 | GPT-6 Astra Pro |
|---|---|---|
| Input price | $3/M tokens | $10/M tokens |
| Output price | $15/M tokens | $50/M tokens |
| Context window | 200K tokens | 1.1M tokens |
| Weights | Closed | Closed |
| Free API (OpenRouter) | No | No |
| Released | May 2025 | Sep 2026 |
Not enough votes to call it. On the specs, GPT-6 Astra Pro has the edge: bigger model tier, newer, bigger context window.
Claude Sonnet 4 costs 3.3x less per token.
Claude Sonnet 4 is cheaper on both: 3.3× input, 3.3× output.
Per million tokens. Prices and uptime via OpenRouter, checked 9 Sep 2026.