Gemini 2.5 Pro vs Gemini 3.1 Flash Lite
Side-by-side benchmark comparison across coding, math, reasoning, speed, and pricing.
Gemini 3.1 Flash Lite by Google wins on 5 of 8 benchmarks against Gemini 2.5 Pro by Google, which leads on 2. This head-to-head comparison covers coding, math, reasoning, speed, and pricing metrics from our benchmark data.
Category-by-Category Breakdown
Coding: In coding, Gemini 2.5 Pro scores 1164 on Design Arena ELO compared to Gemini 3.1 Flash Lite's 1090, while Gemini 2.5 Pro scores 1179 on Website Arena ELO compared to Gemini 3.1 Flash Lite's 1095.
Reasoning: In reasoning, Gemini 3.1 Flash Lite scores 80.1% on GPQA Diamond compared to Gemini 2.5 Pro's 79.9%, while Gemini 3.1 Flash Lite scores 72.3% on τ²-Bench Airline compared to Gemini 2.5 Pro's 61.3%.
Context: In context, both score 1.0M on Context Length.
Pricing Comparison
Gemini 2.5 Pro costs $1.3/1M input tokens and $10.0/1M output tokens, while Gemini 3.1 Flash Lite costs $0.25/1M input and $1.5/1M output. Gemini 3.1 Flash Lite is the more affordable option for API usage.
Verdict
Gemini 3.1 Flash Lite leads across the board in affordability, making it the stronger overall choice in this comparison.
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Gemini 2.5 Pro vs Gemini 3.1 Flash Lite — FAQ
Which is better, Gemini 2.5 Pro or Gemini 3.1 Flash Lite?
Gemini 3.1 Flash Lite wins on more benchmarks overall (5 vs 2). However, the best choice depends on your specific needs — each model excels in different areas.
How does Gemini 2.5 Pro compare to Gemini 3.1 Flash Lite for coding?
SWE-bench Verified data is not available for both models. Check the detailed comparison charts above for other coding-related metrics.
Is Gemini 2.5 Pro cheaper than Gemini 3.1 Flash Lite?
Yes, Gemini 3.1 Flash Lite is cheaper. Gemini 2.5 Pro costs $1.3/1M input and $10.0/1M output tokens. Gemini 3.1 Flash Lite costs $0.25/1M input and $1.5/1M output tokens.
Which is faster, Gemini 2.5 Pro or Gemini 3.1 Flash Lite?
Output speed data is not available for both models. Check the speed section of the comparison above for available performance data.
What benchmarks does the Gemini 2.5 Pro vs Gemini 3.1 Flash Lite comparison cover?
This comparison covers 8 benchmarks including GPQA Diamond, Input Cost, Output Cost, Context Length, Cached Input Cost, Design Arena ELO, τ²-Bench Airline, Website Arena ELO. Metrics span general intelligence, coding, math, reasoning, speed, and cost categories.