Compare AI models

Specifications
Context window
1M—
API pricing
Input price
$2.00$1.75
Output price
$10.00$14.00
Cached input price
$0.20$0.175
Cheapest input
—$1.75Azure
Cheapest output
—$14.00Azure

These models have no shared benchmark scores.

Overview
CompanyAnthropicOpenAI
Release dateSep 28 2026Feb 5 2026
AccessClosedClosed
Model detailsView modelView model

Frequently asked questions

Claude Sonnet 5.5 and GPT-5.3-Codex don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. GPT-5.3-Codex is cheaper on input: $1.75 vs $2.00 per million tokens. Claude Sonnet 5.5 is cheaper on output: $10.00 vs $14.00 per million tokens. GPT-5.3-Codex shipped 235 days before Claude Sonnet 5.5, so benchmark comparisons should account for the intervening progress.

Published specifications for these two models are limited — see each model page for the latest details.

Direct benchmark comparisons are unavailable — Claude Sonnet 5.5 and GPT-5.3-Codex don't publish scores on any of the same benchmarks.