Question 1

What is the difference between Gemini 2.5 Flash Preview 05-20 and Gemini 3.1 Pro Preview?

Accepted Answer

Both are developed by Google AI but target different use cases. Gemini 2.5 Flash Preview 05-20 has a 1.0M token context window vs Gemini 3.1 Pro Preview's 1.0M. in 5 community votes on RIVAL, Gemini 3.1 Pro Preview wins 100% of head-to-head matchups. These results are based on blind head-to-head voting across 11 challenges.

Question 2

Which is better, Gemini 2.5 Flash Preview 05-20 or Gemini 3.1 Pro Preview?

Accepted Answer

Based on 5 community votes on RIVAL, Gemini 3.1 Pro Preview wins 100% of head-to-head matchups against Gemini 2.5 Flash Preview 05-20. Gemini 3.1 Pro Preview is strongest in Web Design, Image Generation.

Question 3

How much does Gemini 2.5 Flash Preview 05-20 cost compared to Gemini 3.1 Pro Preview?

Accepted Answer

Gemini 2.5 Flash Preview 05-20 costs $0.15/M input tokens and Gemini 3.1 Pro Preview costs $2/M input tokens. Gemini 2.5 Flash Preview 05-20 is $1.85/M cheaper per input. The more expensive model wins 100% of duels, so the premium may be justified by quality.

Question 4

How are Gemini 2.5 Flash Preview 05-20 vs Gemini 3.1 Pro Preview votes collected on RIVAL?

Accepted Answer

RIVAL presents both models' outputs side-by-side in blind duels — voters see the responses but don't know which model produced each one. This eliminates brand bias. 5 votes have been collected for this pair across 11 challenges. All vote data is part of RIVAL's open dataset.