Model Comparison

GPT-4.1 mini vs GPT-5.1 InstantWhich is better in 2026?

GPT-5.1 Instant significantly outperforms across most benchmarks. GPT-4.1 mini is 4.9x cheaper per token.

Verdict: GPT-4.1 mini vs GPT-5.1 Instant — which is better?

GPT-4.1 mini (by OpenAI) and GPT-5.1 Instant (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.

GPT-4.1 mini outperforms in 0 benchmarks, while GPT-5.1 Instant is better at 4 benchmarks (AIME 2025, GPQA, MMMU, SWE-Bench Verified). GPT-5.1 Instant significantly outperforms across most benchmarks.

On price, GPT-4.1 mini is roughly 4.9x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

GPT-4.1 mini also accepts a larger context window (1,047,576 input tokens), making it the stronger choice for long documents and large codebases.

Choose GPT-4.1 mini if…

  • cost matters — it's about 4.9x cheaper per token
  • you process long inputs — it offers a 1,047,576 token context window

Choose GPT-5.1 Instant if…

  • you want the strongest raw capability — it leads on 4 of 4 shared benchmarks
  • you want the most recent training data — it shipped Nov 2025

Performance Benchmarks

Comparative analysis across standard metrics

4 benchmarks

GPT-4.1 mini outperforms in 0 benchmarks, while GPT-5.1 Instant is better at 4 benchmarks (AIME 2025, GPQA, MMMU, SWE-Bench Verified).

GPT-5.1 Instant significantly outperforms across most benchmarks.

Mon Jul 27 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

GPT-4.1 mini costs less

For input processing, GPT-4.1 mini ($0.40/1M tokens) is 3.1x cheaper than GPT-5.1 Instant ($1.25/1M tokens).

For output processing, GPT-4.1 mini ($1.60/1M tokens) is 6.3x cheaper than GPT-5.1 Instant ($10.00/1M tokens).

In conclusion, GPT-5.1 Instant is more expensive than GPT-4.1 mini.*

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

Lowest available price from all providers
Mon Jul 27 2026 • llm-stats.com
OpenAI
GPT-4.1 mini
Input tokens$0.40
Output tokens$1.60
Best providerOpenAI
OpenAI
GPT-5.1 Instant
Input tokens$1.25
Output tokens$10.00
Best providerOpenAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

GPT-4.1 mini accepts 1,047,576 input tokens compared to GPT-5.1 Instant's 400,000 tokens. GPT-5.1 Instant can generate longer responses up to 128,000 tokens, while GPT-4.1 mini is limited to 32,768 tokens.

OpenAI
GPT-4.1 mini
Input1,047,576 tokens
Output32,768 tokens
OpenAI
GPT-5.1 Instant
Input400,000 tokens
Output128,000 tokens
Mon Jul 27 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both GPT-4.1 mini and GPT-5.1 Instant support multimodal inputs.

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

GPT-4.1 mini

Text
Images
Audio
Video

GPT-5.1 Instant

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-4.1 mini

Proprietary

Closed source

GPT-5.1 Instant

Proprietary

Closed source

Release Timeline

When each model was launched

GPT-4.1 mini was released on 2025-04-14, while GPT-5.1 Instant was released on 2025-11-12.

GPT-5.1 Instant is 7 months newer than GPT-4.1 mini.

GPT-4.1 mini

Apr 14, 2025

1.3 years ago

GPT-5.1 Instant

Nov 12, 2025

8 months ago

7mo newer

Knowledge Cutoff

When training data ends

GPT-4.1 mini has a documented knowledge cutoff of 2024-05-31, while GPT-5.1 Instant's cutoff date is not specified.

We can confirm GPT-4.1 mini's training data extends to 2024-05-31, but cannot make a direct comparison without GPT-5.1 Instant's cutoff date.

GPT-4.1 mini

May 2024

GPT-5.1 Instant

—

Provider Availability

GPT-4.1 mini is available from OpenAI. GPT-5.1 Instant is available from OpenAI.

GPT-4.1 mini

openai logo
OpenAI
Input Price:Input: $0.40/1MOutput Price:Output: $1.60/1M

GPT-5.1 Instant

openai logo
OpenAI
Input Price:Input: $1.25/1MOutput Price:Output: $10.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

OpenAI
Larger context window (1,047,576 tokens)
Less expensive input tokens
Less expensive output tokens
OpenAI
Higher AIME 2025 score (94.0% vs 40.2%)
Higher GPQA score (88.1% vs 65.0%)
Higher MMMU score (85.4% vs 72.7%)
Higher SWE-Bench Verified score (76.3% vs 23.6%)
OpenAIGPT-4.1 mini
OpenAIGPT-5.1 Instant
Compare in Playground

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against GPT-4.1 mini and GPT-5.1 Instant side-by-side, then vote on the output you prefer.

GPT-4.1 mini
✓ Preferred
GPT-5.1 Instant
Open in Playground
AI Model Comparison Table
Feature
OpenAI
GPT-4.1 mini
OpenAI
GPT-5.1 Instant

FAQ

Common questions about GPT-4.1 mini vs GPT-5.1 Instant.

Which is better, GPT-4.1 mini or GPT-5.1 Instant?

GPT-5.1 Instant significantly outperforms across most benchmarks. GPT-4.1 mini is made by OpenAI and GPT-5.1 Instant is made by OpenAI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does GPT-4.1 mini compare to GPT-5.1 Instant in benchmarks?

GPT-4.1 mini scores CharXiv-D: 88.4%, MMLU: 87.5%, IFEval: 84.1%, MMMLU: 78.5%, MathVista: 73.1%. GPT-5.1 Instant scores Tau2 Telecom: 95.6%, AIME 2025: 94.0%, BrowseComp Long Context 128k: 90.0%, GPQA: 88.1%, MMMU: 85.4%.

Is GPT-4.1 mini cheaper than GPT-5.1 Instant?

GPT-4.1 mini is 3.1x cheaper for input tokens. GPT-4.1 mini costs $0.40/M input and $1.60/M output via openai. GPT-5.1 Instant costs $1.25/M input and $10.00/M output via openai.

What are the context window sizes for GPT-4.1 mini and GPT-5.1 Instant?

GPT-4.1 mini supports 1.0M tokens and GPT-5.1 Instant 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-4.1 mini and GPT-5.1 Instant?

Key differences include context window (1.0M vs 400K), input pricing ($0.40 vs $1.25/M). See the full comparison above for benchmark-by-benchmark results.

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