Gemini 3.1 Pro Preview vs Gemini 3.5 Flash
Compare Gemini 3.1 Pro Preview and Gemini 3.5 Flash, both from Google AI, in 5 community votes, gemini 3.5 flash wins 100% of head-to-head duels, context windows of 1.0M vs 1.0M, tested across 53 shared challenges. Updated June 2026.
Which is better, Gemini 3.1 Pro Preview or Gemini 3.5 Flash?
Gemini 3.5 Flash is the better choice overall, winning 100% of 5 blind community votes on Rival. Gemini 3.1 Pro Preview costs $2/M input tokens vs $1.5/M for Gemini 3.5 Flash. Context windows: 1049K vs 1049K tokens. Compare their real outputs side by side below.
Key Differences Between Gemini 3.1 Pro Preview and Gemini 3.5 Flash
Gemini 3.1 Pro Preview is made by google while Gemini 3.5 Flash is from google. Gemini 3.1 Pro Preview has a 1049K token context window compared to Gemini 3.5 Flash's 1049K. On pricing, Gemini 3.1 Pro Preview costs $2/M input tokens vs $1.5/M for Gemini 3.5 Flash. In community voting, In 5 community votes, Gemini 3.5 Flash wins 100% of head-to-head duels.
In 5 community votes, Gemini 3.5 Flash wins 100% of head-to-head duels. Gemini 3.5 Flash leads in Reasoning, Image Generation. Based on blind community voting from the Rival open dataset of 5+ human preference judgments for this pair.
Per 1M tokens
Gemini 3.5 Flash is cheaper on both — 1.3× input, 1.3× output
Pick Gemini 3.5 Flash. In 5 blind votes, Gemini 3.5 Flash wins 100% of the time. That's not luck.
Gemini 3.5 Flash particularly excels in Reasoning, Image Generation.
Style Comparison
Gemini 3.1 Pro Preview uses 1.8x more hedging
