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Claude Mythos 5.1 vs Jamba 1.5 Large

Claude Mythos 5.1 leads the LLM Stats Score 45.1 to 1.0. Jamba 1.5 Large is 5.7x cheaper per token.

Anthropic · AI21 Labs · Updated for 2026

Which is better?

Claude Mythos 5.1 leads the overall LLM Stats Score 45.1 to 1.0, ranking #31 overall.

On price, Jamba 1.5 Large is roughly 5.7x 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 — 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 Jamba 1.5 Large

  • cost matters — it's about 5.7x cheaper per token
  • you need open weights you can self-host or fine-tune

At a glance

The differences that matter most.

Core performance indexes
45.1
#31
1.0
#320
44.4
#34
1.1
#312
Cost, coverage & limits
Benchmark wins
Input price
$10.00 / M
$2.00 / M
Output price
$50.00 / M
$8.00 / M
Context window
1,000,000
256,000

Individual benchmarks

1 reported for Claude Mythos 5.1 · 8 for Jamba 1.5 Large

No common benchmarks found

Claude Mythos 5.1 and Jamba 1.5 Largedon'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

Jamba 1.5 Large costs less

For input processing, Claude Mythos 5.1 ($10.00/1M tokens) is 5.0x more expensive than Jamba 1.5 Large ($2.00/1M tokens).

For output processing, Claude Mythos 5.1 ($50.00/1M tokens) is 6.3x more expensive than Jamba 1.5 Large ($8.00/1M tokens).

In conclusion, Claude Mythos 5.1 is more expensive than Jamba 1.5 Large.*

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

Lowest available price from all providers
Tue Sep 08 2026 • llm-stats.com
Anthropic
Claude Mythos 5.1
Input tokens$10.00
Output tokens$50.00
Best providerAnthropic
AI21 Labs
Jamba 1.5 Large
Input tokens$2.00
Output tokens$8.00
Best providerAWS Bedrock
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 Jamba 1.5 Large's 256,000 tokens. Jamba 1.5 Large can generate longer responses up to 256,000 tokens, while Claude Mythos 5.1 is limited to 128,000 tokens.

Anthropic
Claude Mythos 5.1
Input1,000,000 tokens
Output128,000 tokens
AI21 Labs
Jamba 1.5 Large
Input256,000 tokens
Output256,000 tokens
Tue Sep 08 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Claude Mythos 5.1 supports multimodal inputs, whereas Jamba 1.5 Large 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

Jamba 1.5 Large

Text
Images
Audio
Video

License

Usage and distribution terms

Claude Mythos 5.1 is licensed under a proprietary license, while Jamba 1.5 Large uses Jamba Open Model License.

License differences may affect how you can use these models in commercial or open-source projects.

Claude Mythos 5.1

Proprietary

Closed source

Jamba 1.5 Large

Jamba Open Model License

Open weights

Release Timeline

When each model was launched

Claude Mythos 5.1 was released on 2026-09-01, while Jamba 1.5 Large was released on 2024-08-22.

Claude Mythos 5.1 is 25 months newer than Jamba 1.5 Large.

Claude Mythos 5.1

Sep 1, 2026

1 weeks ago

2.0yr newer
Jamba 1.5 Large

Aug 22, 2024

2.0 years ago

Knowledge Cutoff

When training data ends

Jamba 1.5 Large has a documented knowledge cutoff of 2024-03-05, while Claude Mythos 5.1's cutoff date is not specified.

We can confirm Jamba 1.5 Large's training data extends to 2024-03-05, but cannot make a direct comparison without Claude Mythos 5.1's cutoff date.

Claude Mythos 5.1

Jamba 1.5 Large

Mar 2024

Provider Availability

Claude Mythos 5.1 is available from Anthropic. Jamba 1.5 Large is available from Bedrock, Google.

Claude Mythos 5.1

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

Jamba 1.5 Large

bedrock logo
AWS Bedrock
Input Price:Input: $2.00/1MOutput Price:Output: $8.00/1M
google logo
Google
Input Price:Input: $2.00/1MOutput Price:Output: $8.00/1M
* 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 Jamba 1.5 Large side-by-side, then vote on the output you prefer.

Claude Mythos 5.1
✓ Preferred
Jamba 1.5 Large
Open in Playground

FAQ

Common questions about Claude Mythos 5.1 vs Jamba 1.5 Large.

Which is better, Claude Mythos 5.1 or Jamba 1.5 Large?

Claude Mythos 5.1 leads the LLM Stats Score 45.1 to 1.0. Claude Mythos 5.1 is made by Anthropic and Jamba 1.5 Large is made by AI21 Labs. 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 Jamba 1.5 Large in benchmarks?

Claude Mythos 5.1 scores Terminal-Bench 4.0: 60.9%. Jamba 1.5 Large scores ARC-C: 93.0%, GSM8k: 87.0%, MMLU: 81.2%, Arena Hard: 65.4%, TruthfulQA: 58.3%.

Is Claude Mythos 5.1 cheaper than Jamba 1.5 Large?

Jamba 1.5 Large is 5.0x cheaper for input tokens. Claude Mythos 5.1 costs $10.00/M input and $50.00/M output via anthropic. Jamba 1.5 Large costs $2.00/M input and $8.00/M output via bedrock.

What are the context window sizes for Claude Mythos 5.1 and Jamba 1.5 Large?

Claude Mythos 5.1 supports 1.0M tokens and Jamba 1.5 Large supports 256K 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 Jamba 1.5 Large?

Key differences include LLM Stats Score (45.1 vs 1.0), context window (1.0M vs 256K), input pricing ($10.00 vs $2.00/M), multimodal support (yes vs no), licensing (Proprietary vs Jamba Open Model License). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Mythos 5.1 and Jamba 1.5 Large?

Claude Mythos 5.1 is developed by Anthropic and Jamba 1.5 Large is developed by AI21 Labs.