Model Comparison

Claude Fable 5 vs Claude Mythos PreviewWhich is better in 2026?

Claude Fable 5 shows notably better performance in the majority of benchmarks. Claude Fable 5 is 2.5x cheaper per token.

Verdict: Claude Fable 5 vs Claude Mythos Preview — which is better?

Claude Fable 5 (by Anthropic) and Claude Mythos Preview (by Anthropic) 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 Fable 5 outperforms in 3 benchmarks (OSWorld-Verified, SWE-Bench Pro, SWE-Bench Verified), while Claude Mythos Preview is better at 1 benchmark (Humanity's Last Exam). Claude Fable 5 shows notably better performance in the majority of benchmarks.

On price, Claude Fable 5 is roughly 2.5x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Choose Claude Fable 5 if…

  • you want the strongest raw capability — it leads on 3 of 4 shared benchmarks
  • cost matters — it's about 2.5x cheaper per token

Choose Claude Mythos Preview if…

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

Performance Benchmarks

Comparative analysis across standard metrics

4 benchmarks

Claude Fable 5 outperforms in 3 benchmarks (OSWorld-Verified, SWE-Bench Pro, SWE-Bench Verified), while Claude Mythos Preview is better at 1 benchmark (Humanity's Last Exam).

Claude Fable 5 shows notably better performance in the majority of benchmarks.

Sat Jul 25 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

Claude Fable 5 costs less

For input processing, Claude Fable 5 ($10.00/1M tokens) is 2.5x cheaper than Claude Mythos Preview ($25.00/1M tokens).

For output processing, Claude Fable 5 ($50.00/1M tokens) is 2.5x cheaper than Claude Mythos Preview ($125.00/1M tokens).

In conclusion, Claude Mythos Preview is more expensive than Claude Fable 5.*

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

Lowest available price from all providers
Sat Jul 25 2026 • llm-stats.com
Anthropic
Claude Fable 5
Input tokens$10.00
Output tokens$50.00
Best providerAnthropic
Anthropic
Claude Mythos Preview
Input tokens$25.00
Output tokens$125.00
Best providerAnthropic
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Only Claude Fable 5 specifies input context (1,000,000 tokens). Only Claude Fable 5 specifies output context (128,000 tokens).

Anthropic
Claude Fable 5
Input1,000,000 tokens
Output128,000 tokens
Anthropic
Claude Mythos Preview
Input- tokens
Output- tokens
Sat Jul 25 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Claude Fable 5 and Claude Mythos Preview support multimodal inputs.

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

Claude Fable 5

Text
Images
Audio
Video

Claude Mythos Preview

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 Fable 5

Proprietary

Closed source

Claude Mythos Preview

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Fable 5 was released on 2026-06-09, while Claude Mythos Preview's release date is not specified.

We can confirm Claude Fable 5's release timeline, but cannot make a direct age comparison without Claude Mythos Preview's release date.

Claude Fable 5

Jun 9, 2026

1 months ago

Claude Mythos Preview

—

Knowledge Cutoff

When training data ends

Neither model specifies a knowledge cutoff date.

Unable to compare the recency of their training data.

No cutoff dates available

Provider Availability

Claude Fable 5 is available from Anthropic. Claude Mythos Preview is available from Anthropic.

Claude Fable 5

anthropic logo
Anthropic
Input Price:Input: $10.00/1MOutput Price:Output: $50.00/1M

Claude Mythos Preview

anthropic logo
Anthropic
Input Price:Input: $25.00/1MOutput Price:Output: $125.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

Anthropic
Larger context window (1,000,000 tokens)
Less expensive input tokens
Less expensive output tokens
Higher OSWorld-Verified score (85.0% vs 79.6%)
Higher SWE-Bench Pro score (80.0% vs 77.8%)
Higher SWE-Bench Verified score (95.0% vs 93.9%)
Anthropic
Higher Humanity's Last Exam score (64.7% vs 64.5%)

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against Claude Fable 5 and Claude Mythos Preview side-by-side, then vote on the output you prefer.

Claude Fable 5
✓ Preferred
Claude Mythos Preview
Open in Playground
AI Model Comparison Table
Feature
Anthropic
Claude Fable 5
Anthropic
Claude Mythos Preview

FAQ

Common questions about Claude Fable 5 vs Claude Mythos Preview.

Which is better, Claude Fable 5 or Claude Mythos Preview?

Claude Fable 5 shows notably better performance in the majority of benchmarks. Claude Fable 5 is made by Anthropic and Claude Mythos Preview is made by Anthropic. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does Claude Fable 5 compare to Claude Mythos Preview in benchmarks?

Claude Fable 5 scores SWE-Bench Verified: 95.0%, FrontierSWE: 90.0%, OSWorld-Verified: 85.0%, Terminal-Bench 2.1: 84.3%, SWE-Bench Pro: 80.0%. Claude Mythos Preview scores CyBench: 100.0%, USAMO25: 97.6%, GPQA: 94.6%, SWE-Bench Verified: 93.9%, CharXiv-R: 93.2%.

Is Claude Fable 5 cheaper than Claude Mythos Preview?

Claude Fable 5 is 2.5x cheaper for input tokens. Claude Fable 5 costs $10.00/M input and $50.00/M output via anthropic. Claude Mythos Preview costs $25.00/M input and $125.00/M output via anthropic.

What are the context window sizes for Claude Fable 5 and Claude Mythos Preview?

Claude Fable 5 supports 1.0M tokens and Claude Mythos Preview supports an unknown number of tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Claude Fable 5 and Claude Mythos Preview?

Key differences include input pricing ($10.00 vs $25.00/M). See the full comparison above for benchmark-by-benchmark results.

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