Claude Opus 4.8 vs OpenAI o3
A direct API-pricing comparison between Claude Opus 4.8 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 — 2.8× less than Claude Opus 4.8 at $0.050.
| Claude Opus 4.8Anthropic | OpenAI o3OpenAI | |
|---|---|---|
| Input / 1M tokens | $5.00 | $2.00 |
| Output / 1M tokens | $25.00 | $8.00 |
| Cached input / 1M | $0.500 | — |
| 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 Opus 4.8 or OpenAI o3?
On output tokens — usually the dominant cost — Claude Opus 4.8 charges $25.00 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.