Model Comparison

GPT-5.1 Codex vs GPT-5.1 Codex MiniWhich is better in 2026?

Comparing GPT-5.1 Codex and GPT-5.1 Codex Mini across benchmarks, pricing, and capabilities.

Verdict: GPT-5.1 Codex vs GPT-5.1 Codex Mini — which is better?

GPT-5.1 Codex (by OpenAI) and GPT-5.1 Codex Mini (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.

On price, GPT-5.1 Codex Mini is roughly 5.0x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Choose GPT-5.1 Codex if…

  • you want the most recent training data — it shipped Nov 2025

Choose GPT-5.1 Codex Mini if…

  • cost matters — it's about 5.0x cheaper per token

Performance Benchmarks

Comparative analysis across standard metrics

No common benchmarks found

GPT-5.1 Codex and GPT-5.1 Codex Minidon't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

GPT-5.1 Codex Mini costs less

For input processing, GPT-5.1 Codex ($1.25/1M tokens) is 5.0x more expensive than GPT-5.1 Codex Mini ($0.25/1M tokens).

For output processing, GPT-5.1 Codex ($10.00/1M tokens) is 5.0x more expensive than GPT-5.1 Codex Mini ($2.00/1M tokens).

In conclusion, GPT-5.1 Codex is more expensive than GPT-5.1 Codex Mini.*

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

Lowest available price from all providers
Fri Jun 26 2026 • llm-stats.com
OpenAI
GPT-5.1 Codex
Input tokens$1.25
Output tokens$10.00
Best providerOpenAI
OpenAI
GPT-5.1 Codex Mini
Input tokens$0.25
Output tokens$2.00
Best providerOpenAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Both models have the same input context window of 400,000 tokens. Both models can generate responses up to 128,000 tokens.

OpenAI
GPT-5.1 Codex
Input400,000 tokens
Output128,000 tokens
OpenAI
GPT-5.1 Codex Mini
Input400,000 tokens
Output128,000 tokens
Fri Jun 26 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both GPT-5.1 Codex and GPT-5.1 Codex Mini support multimodal inputs.

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

GPT-5.1 Codex

Text
Images
Audio
Video

GPT-5.1 Codex 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.

GPT-5.1 Codex

Proprietary

Closed source

GPT-5.1 Codex Mini

Proprietary

Closed source

Release Timeline

When each model was launched

GPT-5.1 Codex was released on 2025-11-19, while GPT-5.1 Codex Mini was released on 2025-11-12.

GPT-5.1 Codex is 0 month newer than GPT-5.1 Codex Mini.

GPT-5.1 Codex

Nov 19, 2025

7 months ago

1w newer
GPT-5.1 Codex Mini

Nov 12, 2025

7 months ago

Knowledge Cutoff

When training data ends

GPT-5.1 Codex has a documented knowledge cutoff of 2024-09-30, while GPT-5.1 Codex Mini's cutoff date is not specified.

We can confirm GPT-5.1 Codex's training data extends to 2024-09-30, but cannot make a direct comparison without GPT-5.1 Codex Mini's cutoff date.

GPT-5.1 Codex

Sep 2024

GPT-5.1 Codex Mini

—

Provider Availability

GPT-5.1 Codex is available from OpenAI. GPT-5.1 Codex Mini is available from OpenAI.

GPT-5.1 Codex

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

GPT-5.1 Codex Mini

openai logo
OpenAI
Input Price:Input: $0.25/1MOutput Price:Output: $2.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

OpenAI

No standout differentiators in the data we have for this pair.

OpenAI
Less expensive input tokens
Less expensive output tokens

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against GPT-5.1 Codex and GPT-5.1 Codex Mini side-by-side, then vote on the output you prefer.

GPT-5.1 Codex
✓ Preferred
GPT-5.1 Codex Mini
Open in Playground
AI Model Comparison Table
Feature
OpenAI
GPT-5.1 Codex
OpenAI
GPT-5.1 Codex Mini

FAQ

Common questions about GPT-5.1 Codex vs GPT-5.1 Codex Mini.

Which is better, GPT-5.1 Codex or GPT-5.1 Codex Mini?

GPT-5.1 Codex (OpenAI) and GPT-5.1 Codex Mini (OpenAI) each have strengths in different areas. Compare their benchmark scores, pricing, context windows, and capabilities above to determine which fits your needs.

How does GPT-5.1 Codex compare to GPT-5.1 Codex Mini in benchmarks?

GPT-5.1 Codex scores SWE-Bench Verified: 73.7%, SWE-Lancer: 66.3%, Terminal-Bench 2.0: 52.8%. GPT-5.1 Codex Mini scores AIME 2025: 42.1%.

Is GPT-5.1 Codex cheaper than GPT-5.1 Codex Mini?

GPT-5.1 Codex Mini is 5.0x cheaper for input tokens. GPT-5.1 Codex costs $1.25/M input and $10.00/M output via openai. GPT-5.1 Codex Mini costs $0.25/M input and $2.00/M output via openai.

What are the context window sizes for GPT-5.1 Codex and GPT-5.1 Codex Mini?

GPT-5.1 Codex supports 400K tokens and GPT-5.1 Codex Mini supports 400K 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 and GPT-5.1 Codex Mini?

Key differences include input pricing ($1.25 vs $0.25/M). See the full comparison above for benchmark-by-benchmark results.

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