Claude Sonnet 4.5 vs OpenAI o4-mini
Compare Claude Sonnet 4.5 by Anthropic against OpenAI o4-mini by OpenAI, tested across 43 shared challenges. Updated May 2026.
Which is better, Claude Sonnet 4.5 or OpenAI o4-mini?
Claude Sonnet 4.5 and OpenAI o4-mini are both competitive models. Claude Sonnet 4.5 costs $3/M input tokens vs $1.1/M for OpenAI o4-mini. Compare their real outputs side by side below.
Key Differences Between Claude Sonnet 4.5 and OpenAI o4-mini
Claude Sonnet 4.5 is made by anthropic while OpenAI o4-mini is from openai. On pricing, Claude Sonnet 4.5 costs $3/M input tokens vs $1.1/M for OpenAI o4-mini.
Per 1M tokens
OpenAI o4-mini is cheaper on both — 2.7× input, 3.4× output
No community votes yet. On paper, Claude Sonnet 4.5 has the edge — bigger model tier, newer, bigger context window.
OpenAI o4-mini is 3.4x cheaper per token — worth considering if cost matters.
Style Comparison
Claude Sonnet 4.5 uses 490.1x more bold
