Claude Mythos 5.1 vs Gemini 1.5 Pro
Claude Mythos 5.1 leads the LLM Stats Score 45.1 to 12.1. Gemini 1.5 Pro is 4.6x cheaper per token.
Anthropic · Google · Updated for 2026
Which is better?
Claude Mythos 5.1 leads the overall LLM Stats Score 45.1 to 12.1, ranking #31 overall.
On price, Gemini 1.5 Pro is roughly 4.6x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
Gemini 1.5 Pro also accepts a larger context window (2,097,152 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 #31 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 1.5 Pro
- cost matters — it's about 4.6x cheaper per token
- you process long inputs — it offers a 2,097,152 token context window
At a glance
The differences that matter most.
Individual benchmarks
1 reported for Claude Mythos 5.1 · 23 for Gemini 1.5 Pro
Claude Mythos 5.1 and Gemini 1.5 Prodon'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 4.0x more expensive than Gemini 1.5 Pro ($2.50/1M tokens).
For output processing, Claude Mythos 5.1 ($50.00/1M tokens) is 5.0x more expensive than Gemini 1.5 Pro ($10.00/1M tokens).
In conclusion, Claude Mythos 5.1 is more expensive than Gemini 1.5 Pro.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
Gemini 1.5 Pro accepts 2,097,152 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 1.5 Pro is limited to 8,192 tokens.
Input capabilities
Documented input modalities across available providers
Both Claude Mythos 5.1 and Gemini 1.5 Pro support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
Claude Mythos 5.1
Gemini 1.5 Pro
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
Claude Mythos 5.1 was released on 2026-09-01, while Gemini 1.5 Pro was released on 2024-05-01.
Claude Mythos 5.1 is 28 months newer than Gemini 1.5 Pro.
Sep 1, 2026
1 weeks ago
2.3yr newerMay 1, 2024
2.4 years ago
Knowledge Cutoff
When training data ends
Gemini 1.5 Pro has a documented knowledge cutoff of 2023-11-01, while Claude Mythos 5.1's cutoff date is not specified.
We can confirm Gemini 1.5 Pro's training data extends to 2023-11-01, but cannot make a direct comparison without Claude Mythos 5.1's cutoff date.
—
Nov 2023
Provider Availability
Claude Mythos 5.1 is available from Anthropic. Gemini 1.5 Pro is available from Google.
Claude Mythos 5.1
Gemini 1.5 Pro
Outputs Comparison
Judge for yourself.
Run your own prompts against Claude Mythos 5.1 and Gemini 1.5 Pro side-by-side, then vote on the output you prefer.
FAQ
Common questions about Claude Mythos 5.1 vs Gemini 1.5 Pro.