GPT-5.1 Instant vs GPT-5.4 mini
GPT-5.1 Instant leads the LLM Stats Score 36.5 to 30.1. GPT-5.4 mini is 2.0x cheaper per token.
OpenAI · OpenAI · Updated for 2026
Which is better?
GPT-5.1 Instant leads the overall LLM Stats Score 36.5 to 30.1, ranking #76 overall.
In the 2 individual benchmarks reported for both models, GPT-5.1 Instant wins 2; this is a narrower head-to-head signal than the composite indexes.
On price, GPT-5.4 mini is roughly 2.0x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.
Choose GPT-5.1 Instant
- overall performance matters — it scores 36.5 and ranks #76 on LLM Stats
- your work emphasizes reasoning — it leads those capability indexes
- you value its reported benchmark strengths — it wins 2 of 2 exact shared results
Choose GPT-5.4 mini
- cost matters — it's about 2.0x cheaper per token
- you want the most recent training data — it shipped Mar 2026
At a glance
The differences that matter most.
Capability indexes
Additional strengths measured across groups of related public benchmarks
Individual benchmarks
9 reported for GPT-5.1 Instant · 15 for GPT-5.4 mini
GPT-5.1 Instant outperforms in 2 benchmarks (GPQA, Tau2 Telecom), while GPT-5.4 mini is better at 0 benchmarks.
GPT-5.1 Instant significantly outperforms across most benchmarks.
Human preference
Blind head-to-head votes and playground preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, GPT-5.1 Instant ($1.25/1M tokens) is 1.7x more expensive than GPT-5.4 mini ($0.75/1M tokens).
For output processing, GPT-5.1 Instant ($10.00/1M tokens) is 2.2x more expensive than GPT-5.4 mini ($4.50/1M tokens).
In conclusion, GPT-5.1 Instant is more expensive than GPT-5.4 mini.*
* Using a 3:1 ratio of input to output tokens
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.
Input capabilities
Documented input modalities across available providers
Both GPT-5.1 Instant and GPT-5.4 mini support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
GPT-5.1 Instant
GPT-5.4 mini
License
Usage and distribution terms
Both models are licensed under proprietary licenses.
Both models have usage restrictions defined by their respective organizations.
Proprietary
Closed source
Proprietary
Closed source
Release Timeline
When each model was launched
GPT-5.1 Instant was released on 2025-11-12, while GPT-5.4 mini was released on 2026-03-17.
GPT-5.4 mini is 4 months newer than GPT-5.1 Instant.
Nov 12, 2025
10 months ago
Mar 17, 2026
6 months ago
4mo newerKnowledge Cutoff
When training data ends
GPT-5.4 mini has a documented knowledge cutoff of 2025-08-31, while GPT-5.1 Instant's cutoff date is not specified.
We can confirm GPT-5.4 mini's training data extends to 2025-08-31, but cannot make a direct comparison without GPT-5.1 Instant's cutoff date.
—
Aug 2025
Provider Availability
GPT-5.1 Instant is available from OpenAI. GPT-5.4 mini is available from OpenAI.
GPT-5.1 Instant
GPT-5.4 mini
Outputs Comparison
Judge for yourself.
Run your own prompts against GPT-5.1 Instant and GPT-5.4 mini side-by-side, then vote on the output you prefer.
FAQ
Common questions about GPT-5.1 Instant vs GPT-5.4 mini.