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Claude Sonnet 5.5 vs Gemini 3.8 Flash

Claude Sonnet 5.5Anthropic
Gemini 3.8 FlashGoogle
Our take

Claude Sonnet 5.5 and Gemini 3.8 Flash trade wins evenly on our provisional scores, but Gemini 3.8 Flash is 2.7× cheaper for customer support replies. Pick Claude Sonnet 5.5 when quality matters most, Gemini 3.8 Flash at volume.

Overall79Best71
Coding87Best66
Writing7480Best
Support6978Best
Value69Best66
Input / 1M$2.00$0.75Best
Output / 1M$10.00$3.75Best
Blended / 1M$4.00$1.50Best
Context window1M1MBest
Open weightsNoNo
Released28 Sept 20262 Sept 2026

Your monthly bill

50k
Claude Sonnet 5.5$800
Gemini 3.8 Flash$300Cheapest
List prices, a quarter of the tokens as output. Scores are provisional, from Arena and Epoch AI.