Anthropic · Claude Opus line · flagship
Claude Opus 4.5 was released by Anthropic on November 24, 2025, as a flagship model in the Claude Opus line.
Opus 4.5 fixes more real software bugs than Opus 4.1 (80.9% vs 74.5% on SWE-bench Verified) and costs two-thirds less, at $5 / $25 per 1M tokens instead of $15 / $75.
Compared with Claude Opus 4.1 · the model it replaces
Fixes about 8 in 10 real software bugs
SWE-bench Verified — fixing real bugs in real software projects
80.9%
▲ up from 74.5% · +6.4 points
Costs a third of what Opus 4.1 cost to run
Price per 1M tokens — what developers pay, input / output
$5 / $25
▲ down from $15 / $75 · two-thirds cheaper
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Claude Opus 5.5 is the current model in this line. The card shows how long it has been since the last release against the line's usual gap and its recent ones — the rhythm, not a date.
Latest: Claude Opus 5.5 · Sep 22, 2026
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