Head to head
o3 vs Claude Sonnet 4
o3 is legacy; Claude Sonnet 4 is retired.
For tasks, about a month.
Verdict · stale basis
o3 costs $0.89 per solved task against
Claude Sonnet 4 at $1.96 — ▼ 2.2x cheaper.
Over 200 tasks that is $214 a month.
On output token price alone o3 looks 1.9x cheaper. The ranking holds, but the margin changes.
Verified pricing, pass rate and cost per solved task for o3 and Claude Sonnet 4| Figure | o3 | Claude Sonnet 4 |
|---|
| Input $/Mtok | $2 | $3 |
|---|
| Output $/Mtok | $8 | $15 |
|---|
| Cached input $/Mtok | $0.5 | $0.3 |
|---|
| Pass rate | 81% | 61% |
|---|
| Cost per solved task | $0.89stale | $1.96stale |
|---|
| Cost per month | $177 | $392 |
|---|
Cost per month against tasks per month · drag the marker
Solid measured · dashed modelled · dotted stale. The gap is the verdict.
Source: Aider polyglot benchmark · verified 2026-08-21 · prices from each provider's pricing page; measured rows ignore the tier · Methodology · All models at these settings