Claude Mythos 5.1 vs Gemini 2.5 Flash-Lite
Claude Mythos 5.1 leads the LLM Stats Score 45.1 to 10.4. Gemini 2.5 Flash-Lite is 114.3x cheaper per token.
Anthropic · Google · Updated for 2026
Which is better?
Claude Mythos 5.1 leads the overall LLM Stats Score 45.1 to 10.4, ranking #33 overall.
On price, Gemini 2.5 Flash-Lite is roughly 114.3x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
Gemini 2.5 Flash-Lite also accepts a larger context window (1,048,576 input tokens), making it the stronger choice for long documents and large codebases.
Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.
Choose Claude Mythos 5.1
- overall performance matters — it scores 45.1 and ranks #33 on LLM Stats
- your work emphasizes reasoning and coding — it leads those capability indexes
- you want the most recent training data — it shipped Sep 2026
Choose Gemini 2.5 Flash-Lite
- cost matters — it's about 114.3x cheaper per token
- you process long inputs — it offers a 1,048,576 token context window
- you need open weights you can self-host or fine-tune
At a glance
The differences that matter most.
Individual benchmarks
1 reported for Claude Mythos 5.1 · 13 for Gemini 2.5 Flash-Lite
Claude Mythos 5.1 and Gemini 2.5 Flash-Litedon'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, Claude Mythos 5.1 ($10.00/1M tokens) is 100.0x more expensive than Gemini 2.5 Flash-Lite ($0.10/1M tokens).
For output processing, Claude Mythos 5.1 ($50.00/1M tokens) is 125.0x more expensive than Gemini 2.5 Flash-Lite ($0.40/1M tokens).
In conclusion, Claude Mythos 5.1 is more expensive than Gemini 2.5 Flash-Lite.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
Gemini 2.5 Flash-Lite accepts 1,048,576 input tokens compared to Claude Mythos 5.1's 1,000,000 tokens. Claude Mythos 5.1 can generate longer responses up to 128,000 tokens, while Gemini 2.5 Flash-Lite is limited to 65,536 tokens.
Input capabilities
Documented input modalities across available providers
Both Claude Mythos 5.1 and Gemini 2.5 Flash-Lite support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
Claude Mythos 5.1
Gemini 2.5 Flash-Lite
License
Usage and distribution terms
Claude Mythos 5.1 is licensed under a proprietary license, while Gemini 2.5 Flash-Lite uses Creative Commons Attribution 4.0 License.
License differences may affect how you can use these models in commercial or open-source projects.
Proprietary
Closed source
Creative Commons Attribution 4.0 License
Open weights
Release Timeline
When each model was launched
Claude Mythos 5.1 was released on 2026-09-01, while Gemini 2.5 Flash-Lite was released on 2025-06-17.
Claude Mythos 5.1 is 15 months newer than Gemini 2.5 Flash-Lite.
Sep 1, 2026
2 weeks ago
1.2yr newerJun 17, 2025
1.3 years ago
Knowledge Cutoff
When training data ends
Gemini 2.5 Flash-Lite has a documented knowledge cutoff of 2025-01-01, while Claude Mythos 5.1's cutoff date is not specified.
We can confirm Gemini 2.5 Flash-Lite's training data extends to 2025-01-01, but cannot make a direct comparison without Claude Mythos 5.1's cutoff date.
—
Jan 2025
Provider Availability
Claude Mythos 5.1 is available from Anthropic. Gemini 2.5 Flash-Lite is available from Google.
Claude Mythos 5.1
Gemini 2.5 Flash-Lite
Outputs Comparison
Judge for yourself.
Run your own prompts against Claude Mythos 5.1 and Gemini 2.5 Flash-Lite side-by-side, then vote on the output you prefer.
FAQ
Common questions about Claude Mythos 5.1 vs Gemini 2.5 Flash-Lite.