Claude Sonnet 4.6 vs OpenAI o3
A direct API-pricing comparison between Claude Sonnet 4.6 and OpenAI o3. Below: every cost dimension side by side, then the bottom line for a typical workload.
Bottom line
For a typical 5K-in / 1K-out request, OpenAI o3 is the cheaper choice at $0.018 per call — 1.7× less than Claude Sonnet 4.6 at $0.030.
| Claude Sonnet 4.6Anthropic | OpenAI o3OpenAI | |
|---|---|---|
| Input / 1M tokens | $3.00 | $2.00 |
| Output / 1M tokens | $15.00 | $8.00 |
| Cached input / 1M | $0.300 | — |
| Context window | 200K | 200K |
| Provider | Anthropic | OpenAI |
Green = cheaper on that line. Prices are estimates from public pricing pages; verify against Anthropic and OpenAI before relying on them.
Which is cheaper, Claude Sonnet 4.6 or OpenAI o3?
On output tokens — usually the dominant cost — Claude Sonnet 4.6 charges $15.00 per million versus $8.00 for OpenAI o3. The right pick depends on your input/output ratio and how much you can serve from cache. Use the calculator to model your exact traffic.