Claude Mythos Preview vs GPT-6 Astra
GPT-6 Astra leads the LLM Stats Score 60.7 to 55.1. GPT-6 Astra is 2.5x cheaper per token.
Anthropic · OpenAI · Updated for 2026
Which is better?
GPT-6 Astra leads the overall LLM Stats Score 60.7 to 55.1, ranking #1 overall.
In the 2 individual benchmarks reported for both models, GPT-6 Astra wins 2; this is a narrower head-to-head signal than the composite indexes.
On price, GPT-6 Astra is roughly 2.5x 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 Claude Mythos Preview
- you want predictable pricing at $25.00/M input and $125.00/M output
Choose GPT-6 Astra
- overall performance matters — it scores 60.7 and ranks #1 on LLM Stats
- your work emphasizes agents — it leads those capability indexes
- you value its reported benchmark strengths — it wins 2 of 2 exact shared results
- cost matters — it's about 2.5x cheaper per token
At a glance
The differences that matter most.
Capability indexes
Additional strengths measured across groups of related public benchmarks
Individual benchmarks
16 reported for Claude Mythos Preview · 22 for GPT-6 Astra
Claude Mythos Preview outperforms in 0 benchmarks, while GPT-6 Astra is better at 2 benchmarks (BrowseComp, GPQA).
GPT-6 Astra significantly outperforms across most benchmarks.
Human preference
Blind head-to-head votes and playground preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, Claude Mythos Preview ($25.00/1M tokens) is 2.5x more expensive than GPT-6 Astra ($10.00/1M tokens).
For output processing, Claude Mythos Preview ($125.00/1M tokens) is 2.5x more expensive than GPT-6 Astra ($50.00/1M tokens).
In conclusion, Claude Mythos Preview is more expensive than GPT-6 Astra.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
Only GPT-6 Astra specifies input context (1,050,000 tokens). Only GPT-6 Astra specifies output context (128,000 tokens).
Input capabilities
Documented input modalities across available providers
Both Claude Mythos Preview and GPT-6 Astra support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
Claude Mythos Preview
GPT-6 Astra
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
GPT-6 Astra was released on 2026-09-03, while Claude Mythos Preview's release date is not specified.
We can confirm GPT-6 Astra's release timeline, but cannot make a direct age comparison without Claude Mythos Preview's release date.
—
Sep 3, 2026
0 days ago
Knowledge Cutoff
When training data ends
GPT-6 Astra has a documented knowledge cutoff of 2026-04-30, while Claude Mythos Preview's cutoff date is not specified.
We can confirm GPT-6 Astra's training data extends to 2026-04-30, but cannot make a direct comparison without Claude Mythos Preview's cutoff date.
—
Apr 2026
Provider Availability
Claude Mythos Preview is available from Anthropic. GPT-6 Astra is available from OpenAI.
Claude Mythos Preview
GPT-6 Astra
Outputs Comparison
Judge for yourself.
Run your own prompts against Claude Mythos Preview and GPT-6 Astra side-by-side, then vote on the output you prefer.
FAQ
Common questions about Claude Mythos Preview vs GPT-6 Astra.