GPT-5.4 mini vs GPT-5.6 Luna
GPT-5.6 Luna leads the LLM Stats Score 45.1 to 30.1. GPT-5.6 Luna is 3.8x cheaper per token.
OpenAI · OpenAI · Updated for 2026
Which is better?
GPT-5.6 Luna leads the overall LLM Stats Score 45.1 to 30.1, ranking #32 overall.
In the 5 individual benchmarks reported for both models, GPT-5.6 Luna wins 5; this is a narrower head-to-head signal than the composite indexes.
On price, GPT-5.6 Luna is roughly 3.8x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
GPT-5.6 Luna also accepts a larger context window (1,050,000 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-5.4 mini
- you want predictable pricing at $0.75/M input and $4.50/M output
Choose GPT-5.6 Luna
- overall performance matters — it scores 45.1 and ranks #32 on LLM Stats
- your work emphasizes reasoning and coding — it leads those capability indexes
- you value its reported benchmark strengths — it wins 5 of 5 exact shared results
- cost matters — it's about 3.8x cheaper per token
- you process long inputs — it offers a 1,050,000 token context window
- you want the most recent training data — it shipped Jul 2026
At a glance
The differences that matter most.
Capability indexes
Additional strengths measured across groups of related public benchmarks
Individual benchmarks
15 reported for GPT-5.4 mini · 45 for GPT-5.6 Luna
GPT-5.4 mini outperforms in 0 benchmarks, while GPT-5.6 Luna is better at 5 benchmarks (GPQA, MMMU-Pro, MRCR v2 (8-needle), SWE-Bench Pro, Toolathlon).
GPT-5.6 Luna 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-5.4 mini ($0.75/1M tokens) is 3.8x more expensive than GPT-5.6 Luna ($0.20/1M tokens).
For output processing, GPT-5.4 mini ($4.50/1M tokens) is 3.8x more expensive than GPT-5.6 Luna ($1.20/1M tokens).
In conclusion, GPT-5.4 mini is more expensive than GPT-5.6 Luna.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
GPT-5.6 Luna accepts 1,050,000 input tokens compared to GPT-5.4 mini's 400,000 tokens. Both models can generate responses up to 128,000 tokens.
Input capabilities
Documented input modalities across available providers
Both GPT-5.4 mini and GPT-5.6 Luna support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
GPT-5.4 mini
GPT-5.6 Luna
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-5.4 mini was released on 2026-03-17, while GPT-5.6 Luna was released on 2026-07-09.
GPT-5.6 Luna is 4 months newer than GPT-5.4 mini.
Mar 17, 2026
6 months ago
Jul 9, 2026
2 months ago
3mo newerKnowledge Cutoff
When training data ends
GPT-5.4 mini has a knowledge cutoff of 2025-08-31, while GPT-5.6 Luna has a cutoff of 2026-02-16.
GPT-5.6 Luna has more recent training data (up to 2026-02-16), making it potentially better informed about events through that date compared to GPT-5.4 mini (2025-08-31).
Aug 2025
Feb 2026
6 mo newerProvider Availability
GPT-5.4 mini is available from OpenAI. GPT-5.6 Luna is available from OpenAI.
GPT-5.4 mini
GPT-5.6 Luna
Outputs Comparison
Judge for yourself.
Run your own prompts against GPT-5.4 mini and GPT-5.6 Luna side-by-side, then vote on the output you prefer.
FAQ
Common questions about GPT-5.4 mini vs GPT-5.6 Luna.