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Claude Mythos 5.1 vs o1-mini

Claude Mythos 5.1 leads the LLM Stats Score 45.1 to 10.1. o1-mini is 3.8x cheaper per token.

Anthropic · OpenAI · Updated for 2026

Which is better?

Claude Mythos 5.1 leads the overall LLM Stats Score 45.1 to 10.1, ranking #31 overall.

On price, o1-mini is roughly 3.8x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Claude Mythos 5.1 also accepts a larger context window (1,000,000 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 process long inputs — it offers a 1,000,000 token context window
  • you want the most recent training data — it shipped Sep 2026

Choose o1-mini

  • cost matters — it's about 3.8x cheaper per token

At a glance

The differences that matter most.

Core performance indexes
45.1
#31
10.1
#264
44.4
#34
10.3
#258
37.5
#17
14.4
#132
Cost, coverage & limits
Benchmark wins
Input price
$10.00 / M
$3.00 / M
Output price
$50.00 / M
$12.00 / M
Context window
1,000,000
128,000

Individual benchmarks

1 reported for Claude Mythos 5.1 · 6 for o1-mini

No common benchmarks found

Claude Mythos 5.1 and o1-minidon'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

o1-mini costs less

For input processing, Claude Mythos 5.1 ($10.00/1M tokens) is 3.3x more expensive than o1-mini ($3.00/1M tokens).

For output processing, Claude Mythos 5.1 ($50.00/1M tokens) is 4.2x more expensive than o1-mini ($12.00/1M tokens).

In conclusion, Claude Mythos 5.1 is more expensive than o1-mini.*

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

Lowest available price from all providers
Wed Sep 09 2026 • llm-stats.com
Anthropic
Claude Mythos 5.1
Input tokens$10.00
Output tokens$50.00
Best providerAnthropic
OpenAI
o1-mini
Input tokens$3.00
Output tokens$12.00
Best providerOpenAI
Notice missing or incorrect data?Start an Issue

Context Window

Maximum input and output token capacity

Claude Mythos 5.1 accepts 1,000,000 input tokens compared to o1-mini's 128,000 tokens. Claude Mythos 5.1 can generate longer responses up to 128,000 tokens, while o1-mini is limited to 65,536 tokens.

Anthropic
Claude Mythos 5.1
Input1,000,000 tokens
Output128,000 tokens
OpenAI
o1-mini
Input128,000 tokens
Output65,536 tokens
Wed Sep 09 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Claude Mythos 5.1 supports multimodal inputs, whereas o1-mini does not.

Claude Mythos 5.1 can handle both text and other forms of data like images, making it suitable for multimodal applications.

Claude Mythos 5.1

Text
Images
Audio
Video

o1-mini

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 5.1

Proprietary

Closed source

o1-mini

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Mythos 5.1 was released on 2026-09-01, while o1-mini was released on 2024-09-12.

Claude Mythos 5.1 is 24 months newer than o1-mini.

Claude Mythos 5.1

Sep 1, 2026

1 weeks ago

2.0yr newer
o1-mini

Sep 12, 2024

2.0 years ago

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 Mythos 5.1 is available from Anthropic. o1-mini is available from OpenAI, Azure.

Claude Mythos 5.1

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

o1-mini

openai logo
OpenAI
Input Price:Input: $3.00/1MOutput Price:Output: $12.00/1M
azure logo
Azure
Input Price:Input: $3.30/1MOutput Price:Output: $13.20/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion

Judge for yourself.

Run your own prompts against Claude Mythos 5.1 and o1-mini side-by-side, then vote on the output you prefer.

Claude Mythos 5.1
✓ Preferred
o1-mini
Open in Playground

FAQ

Common questions about Claude Mythos 5.1 vs o1-mini.

Which is better, Claude Mythos 5.1 or o1-mini?

Claude Mythos 5.1 leads the LLM Stats Score 45.1 to 10.1. Claude Mythos 5.1 is made by Anthropic and o1-mini is made by OpenAI. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Claude Mythos 5.1 compare to o1-mini in benchmarks?

Claude Mythos 5.1 scores Terminal-Bench 4.0: 60.9%. o1-mini scores HumanEval: 92.4%, MATH-500: 90.0%, MMLU: 85.2%, SuperGLUE: 75.0%, GPQA: 60.0%.

Is Claude Mythos 5.1 cheaper than o1-mini?

o1-mini is 3.3x cheaper for input tokens. Claude Mythos 5.1 costs $10.00/M input and $50.00/M output via anthropic. o1-mini costs $3.00/M input and $12.00/M output via openai.

What are the context window sizes for Claude Mythos 5.1 and o1-mini?

Claude Mythos 5.1 supports 1.0M tokens and o1-mini supports 128K 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 5.1 and o1-mini?

Key differences include LLM Stats Score (45.1 vs 10.1), context window (1.0M vs 128K), input pricing ($10.00 vs $3.00/M), multimodal support (yes vs no). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Mythos 5.1 and o1-mini?

Claude Mythos 5.1 is developed by Anthropic and o1-mini is developed by OpenAI.