Skip to content
Seedance 2.0 Face is here — generate video from real-person reference photos.Try it now →
Back to Models
anthropicanthropic·Sep 29, 2025

Anthropic: Claude Sonnet 4.5

anthropic/claude-sonnet-4.5
context
1M
Max Output
64K
Input / 1M
$3.00
Output / 1M
$15.00

About

Claude Sonnet 4.5 is Anthropic's Sonnet model optimized for real-world agents and coding workflows. Anthropic reports 77.2% on SWE-bench Verified for software coding and 61.4% on OSWorld for computer use, with improvements across system design, code security, and specification adherence. The model is designed for extended autonomous operation, maintaining task continuity across sessions, and adds stronger agentic capabilities including improved tool orchestration, speculative parallel execution, and more efficient context and memory management. It accepts text, image, and file input, produces text, and supports a 1,000,000-token context window.

Capabilities

Context Length
1M
Max Output
64K
Reasoning
Yes
In
text, image, file
Out
text

Benchmarks

View leaderboard
43.0#18 of 133
Intelligence Index
38.6#40 of 118
Coding Index
88.0#14 of 63
Math Index

Reasoning & Knowledge

MMLU-Pro87.5%
GPQA Diamond83.4%
HLE17.3%

Coding & Agentic

LiveCodeBench71.4%
SciCode44.7%
Terminal-Bench Hard35.6%

Math

AIME 202588.0%

Source: Artificial Analysis

Pricing

Full pricing
Type≤200K>200K
Input$3.00$6.00
Output$15.00$22.50
Cache Read$0.30$0.60
Cache Write$3.75$7.50
Web Search$0.01 / call

API

API reference

Anthropic-compatible · Model ID anthropic/claude-sonnet-4.5

curl https://api.elliotgate.com/v1/chat/completions \
  -H "Authorization: Bearer sk-omg-your-api-key" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "anthropic/claude-sonnet-4.5",
    "messages": [{"role": "user", "content": "Hello!"}]
  }'

OFTEN COMPARED

Claude Sonnet 4.5 comparisons

Decide which model wins on the dimensions that matter for your workload — context, benchmarks, pricing, or serving latency.