Gemini 2.5 Pro Preview 06-05 vs Gemini 3.8 Flash
Gemini 3.8 Flash leads the LLM Stats Score 51.8 to 30.0. Gemini 3.8 Flash is 2.3x cheaper per token.
Google · Google · Updated for 2026
Which is better?
Gemini 3.8 Flash leads the overall LLM Stats Score 51.8 to 30.0, ranking #11 overall.
On price, Gemini 3.8 Flash is roughly 2.3x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.
Choose Gemini 2.5 Pro Preview 06-05
- you want predictable pricing at $1.25/M input and $10.00/M output
Choose Gemini 3.8 Flash
- overall performance matters — it scores 51.8 and ranks #11 on LLM Stats
- your work emphasizes reasoning and coding — it leads those capability indexes
- cost matters — it's about 2.3x cheaper per token
- you want the most recent training data — it shipped Sep 2026
At a glance
The differences that matter most.
Capability indexes
Additional strengths measured across groups of related public benchmarks
Individual benchmarks
13 reported for Gemini 2.5 Pro Preview 06-05 · 13 for Gemini 3.8 Flash
Gemini 2.5 Pro Preview 06-05 and Gemini 3.8 Flashdon't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.
Human preference
Blind head-to-head votes and playground preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, Gemini 2.5 Pro Preview 06-05 ($1.25/1M tokens) is 1.7x more expensive than Gemini 3.8 Flash ($0.75/1M tokens).
For output processing, Gemini 2.5 Pro Preview 06-05 ($10.00/1M tokens) is 2.7x more expensive than Gemini 3.8 Flash ($3.75/1M tokens).
In conclusion, Gemini 2.5 Pro Preview 06-05 is more expensive than Gemini 3.8 Flash.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
Both models have the same input context window of 1,048,576 tokens. Gemini 3.8 Flash can generate longer responses up to 65,536 tokens, while Gemini 2.5 Pro Preview 06-05 is limited to 65,535 tokens.
Input capabilities
Documented input modalities across available providers
Both Gemini 2.5 Pro Preview 06-05 and Gemini 3.8 Flash support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
Gemini 2.5 Pro Preview 06-05
Gemini 3.8 Flash
License
Usage and distribution terms
Both models are licensed under proprietary licenses.
Both models have usage restrictions defined by their respective organizations.
Proprietary
Closed source
Proprietary
Closed source
Release Timeline
When each model was launched
Gemini 2.5 Pro Preview 06-05 was released on 2025-06-05, while Gemini 3.8 Flash was released on 2026-09-02.
Gemini 3.8 Flash is 15 months newer than Gemini 2.5 Pro Preview 06-05.
Jun 5, 2025
1.2 years ago
Sep 2, 2026
0 days ago
1.2yr newerKnowledge Cutoff
When training data ends
Gemini 2.5 Pro Preview 06-05 has a knowledge cutoff of 2025-01-31, while Gemini 3.8 Flash has a cutoff of 2026-03-31.
Gemini 3.8 Flash has more recent training data (up to 2026-03-31), making it potentially better informed about events through that date compared to Gemini 2.5 Pro Preview 06-05 (2025-01-31).
Jan 2025
Mar 2026
1.2 yr newerProvider Availability
Gemini 2.5 Pro Preview 06-05 is available from Google. Gemini 3.8 Flash is available from Google.
Gemini 2.5 Pro Preview 06-05
Gemini 3.8 Flash
Outputs Comparison
Judge for yourself.
Run your own prompts against Gemini 2.5 Pro Preview 06-05 and Gemini 3.8 Flash side-by-side, then vote on the output you prefer.
FAQ
Common questions about Gemini 2.5 Pro Preview 06-05 vs Gemini 3.8 Flash.