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GPT-5.1 Codex High vs Jamba 1.5 Large

GPT-5.1 Codex High leads the LLM Stats Score 29.4 to 1.1. GPT-5.1 Codex High is 1.0x cheaper per token.

OpenAI · AI21 Labs · Updated for 2026

Which is better?

GPT-5.1 Codex High leads the overall LLM Stats Score 29.4 to 1.1, ranking #120 overall.

GPT-5.1 Codex High also accepts a larger context window (400,000 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 GPT-5.1 Codex High

  • overall performance matters — it scores 29.4 and ranks #120 on LLM Stats
  • your work emphasizes reasoning — it leads those capability indexes
  • you process long inputs — it offers a 400,000 token context window
  • you want the most recent training data — it shipped Nov 2025

Choose Jamba 1.5 Large

  • you need open weights you can self-host or fine-tune

At a glance

The differences that matter most.

Core performance indexes
29.4
#120
1.1
#310
29.2
#114
1.1
#300
Cost, coverage & limits
Benchmark wins
Input price
$1.25 / M
$2.00 / M
Output price
$10.00 / M
$8.00 / M
Context window
400,000
256,000

Individual benchmarks

1 reported for GPT-5.1 Codex High · 8 for Jamba 1.5 Large

No common benchmarks found

GPT-5.1 Codex High 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

GPT-5.1 Codex High costs less

For input processing, GPT-5.1 Codex High ($1.25/1M tokens) is 1.6x cheaper than Jamba 1.5 Large ($2.00/1M tokens).

For output processing, GPT-5.1 Codex High ($10.00/1M tokens) is 1.3x more expensive than Jamba 1.5 Large ($8.00/1M tokens).

In conclusion, Jamba 1.5 Large is more expensive than GPT-5.1 Codex High.*

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

Lowest available price from all providers
Sun Sep 06 2026 • llm-stats.com
OpenAI
GPT-5.1 Codex High
Input tokens$1.25
Output tokens$10.00
Best providerOpenAI
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

GPT-5.1 Codex High accepts 400,000 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 GPT-5.1 Codex High is limited to 128,000 tokens.

OpenAI
GPT-5.1 Codex High
Input400,000 tokens
Output128,000 tokens
AI21 Labs
Jamba 1.5 Large
Input256,000 tokens
Output256,000 tokens
Sun Sep 06 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

GPT-5.1 Codex High supports multimodal inputs, whereas Jamba 1.5 Large does not.

GPT-5.1 Codex High can handle both text and other forms of data like images, making it suitable for multimodal applications.

GPT-5.1 Codex High

Text
Images
Audio
Video

Jamba 1.5 Large

Text
Images
Audio
Video

License

Usage and distribution terms

GPT-5.1 Codex High 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.

GPT-5.1 Codex High

Proprietary

Closed source

Jamba 1.5 Large

Jamba Open Model License

Open weights

Release Timeline

When each model was launched

GPT-5.1 Codex High was released on 2025-11-12, while Jamba 1.5 Large was released on 2024-08-22.

GPT-5.1 Codex High is 15 months newer than Jamba 1.5 Large.

GPT-5.1 Codex High

Nov 12, 2025

9 months ago

1.2yr 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 GPT-5.1 Codex High'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 GPT-5.1 Codex High's cutoff date.

GPT-5.1 Codex High

Jamba 1.5 Large

Mar 2024

Provider Availability

GPT-5.1 Codex High is available from OpenAI. Jamba 1.5 Large is available from Bedrock, Google.

GPT-5.1 Codex High

openai logo
OpenAI
Input Price:Input: $1.25/1MOutput Price:Output: $10.00/1M

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 GPT-5.1 Codex High and Jamba 1.5 Large side-by-side, then vote on the output you prefer.

GPT-5.1 Codex High
✓ Preferred
Jamba 1.5 Large
Open in Playground

FAQ

Common questions about GPT-5.1 Codex High vs Jamba 1.5 Large.

Which is better, GPT-5.1 Codex High or Jamba 1.5 Large?

GPT-5.1 Codex High leads the LLM Stats Score 29.4 to 1.1. GPT-5.1 Codex High is made by OpenAI 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 GPT-5.1 Codex High compare to Jamba 1.5 Large in benchmarks?

GPT-5.1 Codex High scores AIME 2025: 96.7%. Jamba 1.5 Large scores ARC-C: 93.0%, GSM8k: 87.0%, MMLU: 81.2%, Arena Hard: 65.4%, TruthfulQA: 58.3%.

Is GPT-5.1 Codex High cheaper than Jamba 1.5 Large?

GPT-5.1 Codex High is 1.6x cheaper for input tokens. GPT-5.1 Codex High costs $1.25/M input and $10.00/M output via openai. Jamba 1.5 Large costs $2.00/M input and $8.00/M output via bedrock.

What are the context window sizes for GPT-5.1 Codex High and Jamba 1.5 Large?

GPT-5.1 Codex High supports 400K 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 GPT-5.1 Codex High and Jamba 1.5 Large?

Key differences include LLM Stats Score (29.4 vs 1.1), context window (400K vs 256K), input pricing ($1.25 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 GPT-5.1 Codex High and Jamba 1.5 Large?

GPT-5.1 Codex High is developed by OpenAI and Jamba 1.5 Large is developed by AI21 Labs.