AI Model Watch
Models / Anthropic

Claude Sonnet 4.5

GA

API ID claude-sonnet-4-5-20250929 (alias claude-sonnet-4-5). Listed under 'Legacy models' on overview but Active in deprecations table. Extended thinking: Yes; adaptive thinking: No. 200k context, max output 64k. 5m cache $3.75, 1h cache $6, cache hits $0.30/MTok. Batch $1.50/$7.50. Reliable knowledge cutoff Jan 2025; training data cutoff Jul 2025. Snapshot 20250929 implies Sep 29, 2025 release. Tentative retirement not sooner than September 29, 2026.

Provider
Anthropic
Status
GA
Input price
$3 / 1M tokens
Output price
$15 / 1M tokens
Cached input
$0.3 / 1M tokens
Blended price
$6 / 1M tokens
Context window
200,000 tokens (200K)
Max output
64,000 tokens
Modality
text, image, vision
Knowledge cutoff
2025-01
Released
—
API string
claude-sonnet-4-5-20250929

Source: Anthropic official documentation ↗

See also

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