anthropic/claude-sonnet-5

Claude Sonnet 5

Sonnet 5 is Anthropic's most capable Sonnet-class model, with frontier performance across coding, agents, and professional work. It supports adaptive thinking with selectable reasoning effort levels (low, medium, high, max,...

6/30/2026

1,000,000 tokens

#9 Code (Overall)

Input: ¥357.4298/M

Output: ¥1,787.149/M

Try in Chat Get API Key

Specifications

Modalities

Input

text

image

file

Output

text

Supported Parameters

include_reasoning

max_completion_tokens

max_tokens

reasoning

reasoning_effort

response_format

stop

structured_outputs

tool_choice

tools

verbosity

Max Output Tokens

128,000

Code Examples

curl https://api.fastmetal.ai/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -d '{
    "model": "anthropic-claude-sonnet-5",
    "messages": [{"role": "user", "content": "Hello!"}]
  }'

Leaderboard

Text

🏆OverallELO: 1,461

#38

🇯🇵JapaneseELO: 1,477

#12

🇨🇳ChineseELO: 1,500

#42

🇰🇷KoreanELO: 1,421

#38

🇬🇧EnglishELO: 1,470

#39

frenchELO: 1,490

#22

germanELO: 1,438

#64

spanishELO: 1,456

#38

russianELO: 1,461

#39

💻CodingELO: 1,525

#15

🧮MathELO: 1,468

#34

✍️Creative WritingELO: 1,429

#53

📝Instruction FollowingELO: 1,460

#32

🌶️Hard PromptsELO: 1,491

#29

💬Multi-TurnELO: 1,468

#49

Vision

🏆OverallELO: 1,272

#20

Code

🏆OverallELO: 1,544