Claude Sonnet 4.5 vs OpenAI o3
Compare Claude Sonnet 4.5 by Anthropic against OpenAI o3 by OpenAI, in 2 community votes, claude sonnet 4.5 wins 100% of head-to-head duels, tested across 43 shared challenges. Updated May 2026.
Which is better, Claude Sonnet 4.5 or OpenAI o3?
Claude Sonnet 4.5 is the better choice overall, winning 100% of 2 blind community votes on Rival. Claude Sonnet 4.5 costs $3/M input tokens vs $10/M for OpenAI o3. Compare their real outputs side by side below.
Key Differences Between Claude Sonnet 4.5 and OpenAI o3
Claude Sonnet 4.5 is made by anthropic while OpenAI o3 is from openai. On pricing, Claude Sonnet 4.5 costs $3/M input tokens vs $10/M for OpenAI o3. In community voting, In 2 community votes, Claude Sonnet 4.5 wins 100% of head-to-head duels.
In 2 community votes, Claude Sonnet 4.5 wins 100% of head-to-head duels. Based on blind community voting from the Rival open dataset of 2+ human preference judgments for this pair.
Per 1M tokens
Claude Sonnet 4.5 is cheaper on both — 3.3× input, 2.7× output
Pick Claude Sonnet 4.5. In 2 blind votes, Claude Sonnet 4.5 wins 100% of the time. That's not luck.
Style Comparison
Claude Sonnet 4.5 uses 45.2x more emoji
