AI IDE List

Anthropic / Model guide

Claude Opus 5

The previous Opus generation: a baseline for evaluating an Opus 5.5 migration.

Model facts

Context window
1M
Max output
128K
Input / 1M tokens
$5
Output / 1M tokens
$25

Adaptive · high by default. Text and images in; text out. Reviewed 2026-09-25.

Official model documentation

Examples to explore

All 0 examples
No published cases in this collection yet. Explore the Opus 5.5 collection.

API pricing

$5 input · $25 output · $0.5 cache read per million tokens.

Standard API rates. Batch input/output is 50% lower. Cache writes: $6.25 (5 min), $10 (1 hour) per million tokens.

Official pricing

Reported benchmarks

Anthropic launch benchmarks, September 22, 2026
BenchmarkClaude Opus 5
Terminal-Bench 4.0Opus 5.5: xhigh effort52.3%
FrontierCode v1.1Opus 5.5: max effort48%
CursorBench 4.0Opus 5.5: max effort46.6%
GDPval-AA v2.1Opus 5.5: max effort1708 Elo
AutomationBenchOpus 5.5: max effort26.9%
Humanity's Last ExamWith tools · Opus 5.5: max effort63.6%

Vendor-reported launch results, September 22, 2026. Opus 5.5 uses max effort except Terminal-Bench (xhigh). Other models' effort, harness and tool settings can differ; see the original methodology. These are not AI IDE List tests and are separate from Anthropic's medium-effort cost charts.

Benchmark source and methodology

Compare Claude Opus 5

Claude Opus 5.5 vs Claude Opus 5

Opus 5.5 lowers standard input and output token prices by 20%. Use Opus 5 as a baseline and check for regressions on your existing tasks.

View comparison