modelgrep

Anthropic: Claude Sonnet 5 vs OpenAI: GPT-5.5

anthropic logoAnthropic: Claude Sonnet 5anthropic/claude-sonnet-5VSopenai logoOpenAI: GPT-5.5openai/gpt-5.5

OpenAI: GPT-5.5 wins on more metrics (5 of 9), but the right pick depends on what you optimize for — see the breakdown below.

MetricAnthropic: Claude Sonnet 5OpenAI: GPT-5.5
Intelligence Index53.454.8✓
Coding Index71.574.9✓
GPQA Diamond91%94%✓
Design Arena Elo1330✓1300
Speed (tokens/sec)73✓51
Latency2.5s2.0s✓
Input price /M$2.00✓$5.00
Output price /M$10.00✓$30.00
Context window1M1.1M✓
CapabilitiesReasoningToolsJSONVisionReasoningToolsJSONVision
Anthropic: Claude Sonnet 5 details →OpenAI: GPT-5.5 details →