Claude Sonnet 5

Anthropic🇺🇸 United States
active
Context window1000K tokens
Input / 1M tokens$2
Output / 1M tokens$10

Pricing and context window via OpenRouter, 2026-11-13.

Version History

5.0major

Introduces 1M token context, 128K max output, removes sampling parameters (temperature, top_p, top_k), and implements new tokenizer generating ~30% more tokens than Sonnet 4.6 for English text.

5major

Claude Sonnet 5 is Anthropic's first Sonnet model of their latest generation, delivering near-Opus intelligence at Sonnet pricing. Key improvements include stronger multi-step reasoning, improved code navigation, and enhanced agentic reliability for production workflows.

Benchmark Scores

Full leaderboard →
BenchmarkScoreRankSource
Arena Elo1461 Elo41 of 140LMArena, Nov 2026 ↗
GPQA91.1%36 of 163Artificial Analysis, Jul 2026 ↗
SWE-bench Verified79.6%17 of 80Vals AI, Sep 2026 ↗
Speed (tok/s)103 tok/s39 of 101Artificial Analysis, Nov 2026 ↗

Rank is against every model in our database with a sourced score on that benchmark, each counted once with its best score.

Coverage

model releaseAnthropic

Claude Sonnet 5 ships with 1M token context and new tokenizer that increases costs 30-40% for English text

Anthropic released Claude Sonnet 5 with a 1 million token context window and 128,000 token maximum output. The model removes traditional sampling parameters and introduces a new tokenizer that generates approximately 30% more tokens than Sonnet 4.6 for the same English text—effectively a significant price increase despite unchanged nominal rates of $3/million input and $15/million output tokens.

2 min read