Compare Claude Sonnet 4 by Anthropic against Gemini 2.5 Pro (I/O Edition) by Google AI, in 27 community votes, gemini 2.5 pro (i/o edition) wins 63% of head-to-head duels, tested across 41 shared challenges. Updated April 2026.
Gemini 2.5 Pro (I/O Edition) is the better choice overall, winning 63% of 27 blind community votes on Rival. Claude Sonnet 4 costs $3/M input tokens vs $1.25/M for Gemini 2.5 Pro (I/O Edition). Compare their real outputs side by side below.
Claude Sonnet 4 is made by anthropic while Gemini 2.5 Pro (I/O Edition) is from google. On pricing, Claude Sonnet 4 costs $3/M input tokens vs $1.25/M for Gemini 2.5 Pro (I/O Edition). In community voting, In 27 community votes, Gemini 2.5 Pro (I/O Edition) wins 63% of head-to-head duels.
In 27 community votes, Gemini 2.5 Pro (I/O Edition) wins 63% of head-to-head duels. Gemini 2.5 Pro (I/O Edition) leads in Image Generation, Web Design, Reasoning. Based on blind community voting from the Rival open dataset of 27+ human preference judgments for this pair.
Pick Gemini 2.5 Pro (I/O Edition). In 27 blind votes, Gemini 2.5 Pro (I/O Edition) wins 63% of the time. That's not luck.
Gemini 2.5 Pro (I/O Edition) particularly excels in Conversation, Reasoning, Web Design.
Claude Sonnet 4 uses 87.9x more emoji
Ask them anything yourself
Some models write identically. You are paying for the brand.
178 models fingerprinted across 32 writing dimensions. Free research.
185x
price gap between models that write identically
178
models
12
clone pairs
32
dimensions
279 AI models invented the same fake scientist.
We read every word. 250 models. 2.14 million words. This is what we found.

Compare Claude Sonnet 4 by Anthropic against Gemini 2.5 Pro (I/O Edition) by Google AI, in 27 community votes, gemini 2.5 pro (i/o edition) wins 63% of head-to-head duels, tested across 41 shared challenges. Updated April 2026.
Gemini 2.5 Pro (I/O Edition) is the better choice overall, winning 63% of 27 blind community votes on Rival. Claude Sonnet 4 costs $3/M input tokens vs $1.25/M for Gemini 2.5 Pro (I/O Edition). Compare their real outputs side by side below.
Claude Sonnet 4 is made by anthropic while Gemini 2.5 Pro (I/O Edition) is from google. On pricing, Claude Sonnet 4 costs $3/M input tokens vs $1.25/M for Gemini 2.5 Pro (I/O Edition). In community voting, In 27 community votes, Gemini 2.5 Pro (I/O Edition) wins 63% of head-to-head duels.
In 27 community votes, Gemini 2.5 Pro (I/O Edition) wins 63% of head-to-head duels. Gemini 2.5 Pro (I/O Edition) leads in Image Generation, Web Design, Reasoning. Based on blind community voting from the Rival open dataset of 27+ human preference judgments for this pair.
Pick Gemini 2.5 Pro (I/O Edition). In 27 blind votes, Gemini 2.5 Pro (I/O Edition) wins 63% of the time. That's not luck.
Gemini 2.5 Pro (I/O Edition) particularly excels in Conversation, Reasoning, Web Design.
Claude Sonnet 4 uses 87.9x more emoji
Ask them anything yourself
Some models write identically. You are paying for the brand.
178 models fingerprinted across 32 writing dimensions. Free research.
185x
price gap between models that write identically
178
models
12
clone pairs
32
dimensions
279 AI models invented the same fake scientist.
We read every word. 250 models. 2.14 million words. This is what we found.

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24+ more head-to-head results. Free. Not a trick.
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36 fights queued
24+ more head-to-head results. Free. Not a trick.
Free account. No card required. By continuing, you agree to Rival's Terms and Privacy Policy