Claude Opus 5 vs Claude Opus 4.8

Source-checked evaluation entries, evidence gaps and checked price quotes where available.

Claude Opus 5

Anthropic
Text Arena1490 ± 4

Claude Opus 5 (High). Board 2026-10-20; checked 2026-10-22.

Composite / MMLU estimatesWithheld
Standard short-context input quote / 1M tokens$5

Anthropic pricing · checked 2026-10-22. Context tiers and cache-hit rates may differ.

Claude Opus 4.8

Anthropic
Text Arena1474 ± 4

Claude Opus 4.8. Board 2026-10-20; checked 2026-10-22.

Composite / MMLU estimatesWithheld
Standard short-context input quote / 1M tokens$5

Anthropic pricing · checked 2026-10-22. Context tiers and cache-hit rates may differ.

What the evidence supports

The recorded entries are Claude Opus 5 (High) (1490 ± 4) and Claude Opus 4.8 (1474 ± 4).

Their point estimates differ by 16 points. The displayed ranges do not overlap; this is not a test of task-specific superiority or a guarantee about a different configuration.

The former composite, MMLU and cost-per-capability recommendations are withdrawn because their inputs included unsupported estimates. No upgrade or overall capability recommendation is made from those numbers.

Price quotes are from the selected provider registry checked 2026-10-22. Unverified legacy quotes are withheld. Use the token calculator for input, output, cache-hit and context-tier scenarios. Additional service charges and account-specific terms can change a bill. Missing pricing evidence does not mean free inference.

Reporting on Anthropic