Model Comparison

Claude Mythos Preview vs GPT-5.6 SolWhich is better in 2026?

GPT-5.6 Sol has a slight edge in benchmark performance. GPT-5.6 Sol is 4.4x cheaper per token.

Verdict: Claude Mythos Preview vs GPT-5.6 Sol — which is better?

Claude Mythos Preview (by Anthropic) and GPT-5.6 Sol (by OpenAI) are two of the AI models people compare most. Here is how they stack up on benchmarks, price and capabilities, and which one to pick in 2026.

Claude Mythos Preview outperforms in 1 benchmarks (SWE-Bench Pro), while GPT-5.6 Sol is better at 2 benchmarks (BrowseComp, Graphwalks BFS >128k). GPT-5.6 Sol has a slight edge in benchmark performance.

On price, GPT-5.6 Sol is roughly 4.4x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Choose Claude Mythos Preview if…

  • you want predictable pricing at $25.00/M input and $125.00/M output

Choose GPT-5.6 Sol if…

  • you want the strongest raw capability — it leads on 3 of 4 shared benchmarks
  • cost matters — it's about 4.4x cheaper per token

Performance Benchmarks

Comparative analysis across standard metrics

4 benchmarks

Claude Mythos Preview outperforms in 1 benchmarks (SWE-Bench Pro), while GPT-5.6 Sol is better at 2 benchmarks (BrowseComp, Graphwalks BFS >128k).

GPT-5.6 Sol has a slight edge in benchmark performance.

Wed Jul 22 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

GPT-5.6 Sol costs less

For input processing, Claude Mythos Preview ($25.00/1M tokens) is 5.0x more expensive than GPT-5.6 Sol ($5.00/1M tokens).

For output processing, Claude Mythos Preview ($125.00/1M tokens) is 4.2x more expensive than GPT-5.6 Sol ($30.00/1M tokens).

In conclusion, Claude Mythos Preview is more expensive than GPT-5.6 Sol.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Wed Jul 22 2026 • llm-stats.com
Anthropic
Claude Mythos Preview
Input tokens$25.00
Output tokens$125.00
Best providerAnthropic
OpenAI
GPT-5.6 Sol
Input tokens$5.00
Output tokens$30.00
Best providerOpenAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Only GPT-5.6 Sol specifies input context (1,050,000 tokens). Only GPT-5.6 Sol specifies output context (128,000 tokens).

Anthropic
Claude Mythos Preview
Input- tokens
Output- tokens
OpenAI
GPT-5.6 Sol
Input1,050,000 tokens
Output128,000 tokens
Wed Jul 22 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Claude Mythos Preview and GPT-5.6 Sol support multimodal inputs.

They are both capable of processing various types of data, offering versatility in application.

Claude Mythos Preview

Text
Images
Audio
Video

GPT-5.6 Sol

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

Claude Mythos Preview

Proprietary

Closed source

GPT-5.6 Sol

Proprietary

Closed source

Release Timeline

When each model was launched

GPT-5.6 Sol was released on 2026-07-09, while Claude Mythos Preview's release date is not specified.

We can confirm GPT-5.6 Sol's release timeline, but cannot make a direct age comparison without Claude Mythos Preview's release date.

Claude Mythos Preview

—

GPT-5.6 Sol

Jul 9, 2026

1 weeks ago

Knowledge Cutoff

When training data ends

GPT-5.6 Sol has a documented knowledge cutoff of 2026-02-16, while Claude Mythos Preview's cutoff date is not specified.

We can confirm GPT-5.6 Sol's training data extends to 2026-02-16, but cannot make a direct comparison without Claude Mythos Preview's cutoff date.

Claude Mythos Preview

—

GPT-5.6 Sol

Feb 2026

Provider Availability

Claude Mythos Preview is available from Anthropic. GPT-5.6 Sol is available from OpenAI.

Claude Mythos Preview

anthropic logo
Anthropic
Input Price:Input: $25.00/1MOutput Price:Output: $125.00/1M

GPT-5.6 Sol

openai logo
OpenAI
Input Price:Input: $5.00/1MOutput Price:Output: $30.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

Anthropic
Higher SWE-Bench Pro score (77.8% vs 64.6%)
OpenAI
Larger context window (1,050,000 tokens)
Less expensive input tokens
Less expensive output tokens
Higher BrowseComp score (90.4% vs 86.9%)
Higher Graphwalks BFS >128k score (90.7% vs 80.0%)

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against Claude Mythos Preview and GPT-5.6 Sol side-by-side, then vote on the output you prefer.

Claude Mythos Preview
✓ Preferred
GPT-5.6 Sol
Open in Playground
AI Model Comparison Table
Feature
Anthropic
Claude Mythos Preview
OpenAI
GPT-5.6 Sol

FAQ

Common questions about Claude Mythos Preview vs GPT-5.6 Sol.

Which is better, Claude Mythos Preview or GPT-5.6 Sol?

GPT-5.6 Sol has a slight edge in benchmark performance. Claude Mythos Preview is made by Anthropic and GPT-5.6 Sol is made by OpenAI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does Claude Mythos Preview compare to GPT-5.6 Sol in benchmarks?

Claude Mythos Preview scores CyBench: 100.0%, USAMO25: 97.6%, GPQA: 94.6%, SWE-Bench Verified: 93.9%, CharXiv-R: 93.2%. GPT-5.6 Sol scores Connectors: 100.0%, Capture-the-Flag Challenges (Internal): 96.7%, HealthBench Consensus: 95.5%, GPQA: 94.6%, MRCR v2 (8-needle): 91.5%.

Is Claude Mythos Preview cheaper than GPT-5.6 Sol?

GPT-5.6 Sol is 5.0x cheaper for input tokens. Claude Mythos Preview costs $25.00/M input and $125.00/M output via anthropic. GPT-5.6 Sol costs $5.00/M input and $30.00/M output via openai.

What are the context window sizes for Claude Mythos Preview and GPT-5.6 Sol?

Claude Mythos Preview supports an unknown number of tokens and GPT-5.6 Sol supports 1.1M tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Claude Mythos Preview and GPT-5.6 Sol?

Key differences include input pricing ($25.00 vs $5.00/M). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Mythos Preview and GPT-5.6 Sol?

Claude Mythos Preview is developed by Anthropic and GPT-5.6 Sol is developed by OpenAI.

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