GPT-5.4 Mini vs GPT-5.6 Luna
Updated October 21, 2026. 80 benchmarks have a result for both. Coding is ranked on the Vibe Coding Index; every other board is shown as published.
Decision reading
Pick GPT-5.6 Luna for coding: it scores 61.5 on the Vibe Coding Index against 28.2 for GPT-5.4 Mini.
Pick GPT-5.4 Mini when what matters is LMArena Vision: homework or SAGE (Vals AI), where it leads.
- Shared results
- 80
- GPT-5.4 Mini only
- 8
- GPT-5.6 Luna only
- 36
- Like-for-like categories
- 7 of 9
Shared results can support a head-to-head reading. Results only one model has describe coverage, not superiority.
Which one for your work
Each card is decided by one number both models carry. Where only one has it, the card says so and makes no call.
Coding
Vibe Coding Index, four public coding benchmarks
GPT-5.6 Luna
GPT-5.6 Luna scores 61.5 against 28.2.
1 and 2 benchmarks behind the scores
Intelligence
AA Intelligence Index
GPT-5.6 Luna
GPT-5.6 Luna leads, 37.3 against 24.1.
Same board, both measured
Agentic work
AA Agentic Index
GPT-5.6 Luna
GPT-5.6 Luna leads, 42.1 against 17.9.
Same board, both measured
Reasoning
GPQA Diamond
GPT-5.6 Luna
GPT-5.6 Luna leads, 91.7% against 83.1%.
Same board, both measured
Math
AIME
No call
Only GPT-5.4 Mini has a AIME result, 95.6%.
Directional only
Knowledge
MMLU Pro
GPT-5.6 Luna
GPT-5.6 Luna leads, 86.0% against 84.5%.
Same board, both measured
Web design
Design Arena: websites
No call
Only GPT-5.6 Luna has a Design Arena: websites result, 1256.
Directional only
Long documents
Listed context window
GPT-5.6 Luna
GPT-5.6 Luna takes 1.05M tokens against 400K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
GPT-5.6 Luna
GPT-5.4 Mini $0.0030, GPT-5.6 Luna $0.0008 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
GPT-5.6 Luna
GPT-5.4 Mini $0.70, GPT-5.6 Luna $0.04.
Published attempt cost and pass rate
At a glance
- Coding index
- GPT-5.4 Mini 28.2 from 1 benchmark, GPT-5.6 Luna 61.5 from 2 benchmarks.
- Widest category
- Math, 24.0 points apart on average over 6 shared benchmarks.
- Widest single gap
- FrontierMath, tier 4: GPT-5.4 Mini 9.8% against GPT-5.6 Luna 61.0%, 51.2 points apart on a 0 to 100 scale.
- Output price
- GPT-5.4 Mini $4.50 against GPT-5.6 Luna $1.20 per million output tokens, 3.8x apart.
- Context window
- GPT-5.4 Mini takes 400K tokens, GPT-5.6 Luna 1.05M.
Benchmark by benchmark
First the score: boards each model leads, per category, where both have a result. Then every board, a category to a fold; bars are each result on a 0 to 100 scale, so compare the two in a row, not one row with another.
| Category | GPT-5.4 Mini | Bars | GPT-5.6 Luna | Ties |
|---|---|---|---|---|
| Coding | 0 | 15 | 1 tie | |
| Intelligence | 0 | 2 | ||
| Agentic work | 0 | 5 | ||
| Reasoning | 1 | 13 | ||
| Math | 0 | 6 | ||
| Knowledge | 0 | 9 | ||
| General | 3 | 25 | ||
| All shared boards | 4 | 75 | 1 tie |
CodingLike-for-likeFour of these boards feed the Vibe Coding Index015
| Benchmark | GPT-5.4 Mini | GPT-5.6 Luna | Leader |
|---|---|---|---|
| LiveBench coding | Not measured | 73.6% | Only GPT-5.6 Luna measured |
| LMArena WebDev | 1397 | 1518 | GPT-5.6 Luna |
| AA Coding Index | 56.1 | 71.4 | GPT-5.6 Luna |
| LiveCodeBench (Vals AI) | 81.5% | Not measured | Only GPT-5.4 Mini measured |
| SWE-bench Verified (Vals AI) | 73.0% | 93.0% | GPT-5.6 Luna |
| Terminal-Bench 4 (Vals AI) | 2.5% | 11.6% | GPT-5.6 Luna |
| Vibe Code Bench (Vals AI) | 48.0% | 77.1% | GPT-5.6 Luna |
| Code migration (Vals AI) | 12.9% | 44.5% | GPT-5.6 Luna |
| ProgramBench (Vals AI) | 0.0% | 0.0% | Tie |
| IOI (Vals AI) | Not measured | 61.8% | Only GPT-5.6 Luna measured |
| Terminal-Bench 2.1 (Vals AI) | 54.7% | 79.0% | GPT-5.6 Luna |
| Vibe Code Bench 1-100 (Vals AI) | Not measured | 22.6% | Only GPT-5.6 Luna measured |
| SkillsBench (Vals AI) | Not measured | 60.5% | Only GPT-5.6 Luna measured |
| CyberBench (Vals AI) | Not measured | 73.6% | Only GPT-5.6 Luna measured |
| SciCode | 52.1% | 53.6% | GPT-5.6 Luna |
| Terminal-Bench Hard (Artificial Analysis run) | 52.3% | Not measured | Only GPT-5.4 Mini measured |
| FrontierCode | 27.0% | 39.8% | GPT-5.6 Luna |
| WeirdML | 60.3% | 60.9% | GPT-5.6 Luna |
| ALE-Bench | 1188.6 | 1667.4 | GPT-5.6 Luna |
| LMArena Text: coding | 1438 | 1466 | GPT-5.6 Luna |
| LMArena Text: software and IT | 1436 | 1463 | GPT-5.6 Luna |
| LMArena WebDev: React | 1386 | 1508 | GPT-5.6 Luna |
| LMArena WebDev: HTML | 1419 | 1520 | GPT-5.6 Luna |
| LMArena WebDev: from an image | Not measured | 1517 | Only GPT-5.6 Luna measured |
| Neither model has a result on the other 14 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index02
| Benchmark | GPT-5.4 Mini | GPT-5.6 Luna | Leader |
|---|---|---|---|
| AA Intelligence Index | 24.1 | 37.3 | GPT-5.6 Luna |
| Epoch Capabilities Index | 148.7 | 156.5 | GPT-5.6 Luna |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index05
| Benchmark | GPT-5.4 Mini | GPT-5.6 Luna | Leader |
|---|---|---|---|
| AA Agentic Index | 17.9 | 42.1 | GPT-5.6 Luna |
| LiveBench research | Not measured | 51.0% | Only GPT-5.6 Luna measured |
| LiveBench browser | Not measured | 68.0% | Only GPT-5.6 Luna measured |
| LiveBench long agentic | Not measured | 30.4% | Only GPT-5.6 Luna measured |
| SREBench (Vals AI) | Not measured | 1.5% | Only GPT-5.6 Luna measured |
| Finance Agent (Vals AI) | 45.4% | 55.0% | GPT-5.6 Luna |
| Tax Agent Bench (Vals AI) | 8.8% | 24.8% | GPT-5.6 Luna |
| Legal Research Bench (Vals AI) | 12.5% | 36.5% | GPT-5.6 Luna |
| Excel Modeling Benchmark (Vals AI) | 45.4% | 67.1% | GPT-5.6 Luna |
| BioMysteryBench (Vals AI) | Not measured | 61.5% | Only GPT-5.6 Luna measured |
| Terminal-Bench-Science (Vals AI) | Not measured | 0.0% | Only GPT-5.6 Luna measured |
| Vals Science Index | Not measured | 25.3% | Only GPT-5.6 Luna measured |
| τ²-Bench Telecom | 83.3% | Not measured | Only GPT-5.4 Mini measured |
| APEX-Agents | Not measured | 43.0% | Only GPT-5.6 Luna measured |
| BALROG | Not measured | 45.6% | Only GPT-5.6 Luna measured |
| DeepResearch Bench | 36.3% | Not measured | Only GPT-5.4 Mini measured |
| Vending-Bench 2 | Not measured | $4,095 | Only GPT-5.6 Luna measured |
| Neither model has a result on the other 22 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index113
| Benchmark | GPT-5.4 Mini | GPT-5.6 Luna | Leader |
|---|---|---|---|
| GPQA Diamond | 83.1% | 91.7% | GPT-5.6 Luna |
| LiveBench reasoning | Not measured | 85.6% | Only GPT-5.6 Luna measured |
| MysteryMechanism (Vals AI) | Not measured | 14.4% | Only GPT-5.6 Luna measured |
| MMMU Pro (Vals AI) | 79.3% | 85.0% | GPT-5.6 Luna |
| GPQA Diamond (Artificial Analysis run) | 87.5% | 91.1% | GPT-5.6 Luna |
| Humanity's Last Exam (Artificial Analysis run) | 28.1% | 39.5% | GPT-5.6 Luna |
| GPQA Diamond (Epoch AI run) | 86.9% | 91.6% | GPT-5.6 Luna |
| ARC-AGI | 63.7% | 88.0% | GPT-5.6 Luna |
| ARC-AGI-2 | 18.9% | 59.5% | GPT-5.6 Luna |
| SimpleBench | Not measured | 46.8% | Only GPT-5.6 Luna measured |
| Chess puzzles | 23.0% | 43.0% | GPT-5.6 Luna |
| Mystery game puzzles | 11.0% | 21.0% | GPT-5.6 Luna |
| LMArena Text: hard prompts | 1424 | 1451 | GPT-5.6 Luna |
| LMArena Text: expert | 1435 | 1478 | GPT-5.6 Luna |
| LMArena Text: hard prompts in English | 1420 | 1460 | GPT-5.6 Luna |
| LMArena Vision: diagrams | 1266 | 1273 | GPT-5.6 Luna |
| LMArena Vision: homework | 1285 | 1282 | GPT-5.4 Mini |
| Neither model has a result on the other 4 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index06
| Benchmark | GPT-5.4 Mini | GPT-5.6 Luna | Leader |
|---|---|---|---|
| AIME | 95.6% | Not measured | Only GPT-5.4 Mini measured |
| OTIS Mock AIME | 88.9% | 98.3% | GPT-5.6 Luna |
| FrontierMath, tiers 1 to 3 | 51.2% | 82.1% | GPT-5.6 Luna |
| FrontierMath, tier 4 | 9.8% | 61.0% | GPT-5.6 Luna |
| ProofBench | 21.0% | 60.0% | GPT-5.6 Luna |
| LMArena Text: math | 1418 | 1459 | GPT-5.6 Luna |
| LMArena Text: mathematical work | 1429 | 1470 | GPT-5.6 Luna |
| Neither model has a result on the other 6 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index09
| Benchmark | GPT-5.4 Mini | GPT-5.6 Luna | Leader |
|---|---|---|---|
| MMLU Pro | 84.5% | 86.0% | GPT-5.6 Luna |
| LegalBench (Vals AI) | Not measured | 84.0% | Only GPT-5.6 Luna measured |
| CaseLaw (Vals AI) | 51.7% | Not measured | Only GPT-5.4 Mini measured |
| CorpFin (Vals AI) | 60.9% | 64.2% | GPT-5.6 Luna |
| TaxEval (Vals AI) | 71.2% | 76.2% | GPT-5.6 Luna |
| MortgageTax (Vals AI) | 63.5% | 67.3% | GPT-5.6 Luna |
| MedCode (Vals AI) | Not measured | 42.4% | Only GPT-5.6 Luna measured |
| SimpleQA Verified | 29.4% | 41.0% | GPT-5.6 Luna |
| LMArena Text: science | 1417 | 1433 | GPT-5.6 Luna |
| LMArena Text: medicine and healthcare | 1395 | 1399 | GPT-5.6 Luna |
| LMArena Text: legal and government | 1414 | 1446 | GPT-5.6 Luna |
| LMArena Text: business and finance | 1418 | 1439 | GPT-5.6 Luna |
| Neither model has a result on the other 5 boards here | |||
Web designDirectional onlyPublic boards, shown as published, kept out of the index9 boards, none shared
| Benchmark | GPT-5.4 Mini | GPT-5.6 Luna | Leader |
|---|---|---|---|
| Design Arena: websites | Not measured | 1256 | Only GPT-5.6 Luna measured |
| Design Arena: UI components | Not measured | 1250 | Only GPT-5.6 Luna measured |
| Design Arena: game dev | Not measured | 1196 | Only GPT-5.6 Luna measured |
| Design Arena: data viz | Not measured | 1212 | Only GPT-5.6 Luna measured |
| Design Arena: 3D | Not measured | 1121 | Only GPT-5.6 Luna measured |
| Design Arena: all code categories | Not measured | 1231 | Only GPT-5.6 Luna measured |
| Design Arena: SVG | Not measured | 1193 | Only GPT-5.6 Luna measured |
| Design Arena: ASCII art | Not measured | 1144 | Only GPT-5.6 Luna measured |
| LiveBench design | Not measured | 76.0% | Only GPT-5.6 Luna measured |
GeneralLike-for-likePublic boards, shown as published, kept out of the index325
| Benchmark | GPT-5.4 Mini | GPT-5.6 Luna | Leader |
|---|---|---|---|
| LiveBench data analysis | Not measured | 78.0% | Only GPT-5.6 Luna measured |
| Public Benefits Bench (Vals AI) | Not measured | 61.2% | Only GPT-5.6 Luna measured |
| SAGE (Vals AI) | 50.8% | 44.2% | GPT-5.4 Mini |
| MedScribe (Vals AI) | Not measured | 84.4% | Only GPT-5.6 Luna measured |
| Vals Multimodal Index | 54.2% | 69.1% | GPT-5.6 Luna |
| IFBench | 73.3% | Not measured | Only GPT-5.4 Mini measured |
| Long context reasoning (AA-LCR) | 77.0% | 83.7% | GPT-5.6 Luna |
| DTBench | 80.0% | 89.1% | GPT-5.6 Luna |
| LMCA | 40.8% | 48.5% | GPT-5.6 Luna |
| Surface Evolver Bench | Not measured | 61.9% | Only GPT-5.6 Luna measured |
| Furniture assembly | Not measured | 42.5% | Only GPT-5.6 Luna measured |
| LMArena Text | 1412 | 1431 | GPT-5.6 Luna |
| LMArena Text: instruction following | 1405 | 1437 | GPT-5.6 Luna |
| LMArena Text: creative writing | 1370 | 1396 | GPT-5.6 Luna |
| LMArena Vision | 1245 | 1257 | GPT-5.6 Luna |
| LMArena Text: English | 1412 | 1441 | GPT-5.6 Luna |
| LMArena Text: non-English | 1405 | 1417 | GPT-5.6 Luna |
| LMArena Text: Chinese | 1446 | 1470 | GPT-5.6 Luna |
| LMArena Text: German | 1408 | 1455 | GPT-5.6 Luna |
| LMArena Text: Japanese | 1375 | 1415 | GPT-5.6 Luna |
| LMArena Text: Korean | 1370 | 1415 | GPT-5.6 Luna |
| LMArena Text: French | 1441 | 1458 | GPT-5.6 Luna |
| LMArena Text: Spanish | 1405 | 1446 | GPT-5.6 Luna |
| LMArena Text: Russian | 1417 | 1427 | GPT-5.6 Luna |
| LMArena Text: Polish | 1415 | 1405 | GPT-5.4 Mini |
| LMArena Text: multi-turn | 1429 | 1434 | GPT-5.6 Luna |
| LMArena Text: longer queries | 1408 | 1436 | GPT-5.6 Luna |
| LMArena Text: writing and language | 1393 | 1419 | GPT-5.6 Luna |
| LMArena Text: entertainment and media | 1373 | 1402 | GPT-5.6 Luna |
| LMArena Vision: English | 1244 | 1263 | GPT-5.6 Luna |
| LMArena Vision: Chinese | 1286 | 1294 | GPT-5.6 Luna |
| LMArena Vision: reading text | 1253 | 1264 | GPT-5.6 Luna |
| LMArena Vision: humor | 1235 | 1190 | GPT-5.4 Mini |
| LMArena Vision: recognizing things | 1218 | Not measured | Only GPT-5.4 Mini measured |
| LMArena Vision: creative writing | 1222 | 1257 | GPT-5.6 Luna |
| LMArena Document | Not measured | 1457 | Only GPT-5.6 Luna measured |
| Neither model has a result on the other 10 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | GPT-5.4 Mini | GPT-5.6 Luna | Leader |
|---|---|---|---|
| Neither model has a result on 5 boards here | |||
What each workload costs
Three fixed token mixes at each model's listed price, so per-token rates become a bill.
Chat turn
1K input + 500 output tokens
GPT-5.6 Luna costs less
Repository review
50K input + 3K output tokens
GPT-5.6 Luna costs less
Agent loop
200K input + 10K output tokens
GPT-5.6 Luna costs less
Listed OpenRouter rates, without cache or batch discounts. A workload that does not fit a model's context window would need splitting.
Specification differences
The leading value in a row is marked; a row with a missing value names no leader. Our two rows are marked in red.
| Specification | OpenAI GPT-5.4 Mini | OpenAI GPT-5.6 Luna |
|---|---|---|
| Maker | OpenAI | OpenAI |
| Weights | No public weights listed | No public weights listed |
| Released | March 17, 2026 | July 9, 2026 |
| Context window | 400K | 1.05M |
| Input $/Mtok | $0.75 | $0.20 |
| Output $/Mtok | $4.50 | $1.20 |
| Coding index | 28.2 | 61.5 |
| Independent measurements behind it | 1 | 2 |
| Cost per solved task | $0.70 | $0.04 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is GPT-5.4 Mini better than GPT-5.6 Luna for coding?
Pick GPT-5.6 Luna for coding: it scores 61.5 on the Vibe Coding Index against 28.2 for GPT-5.4 Mini. Pick GPT-5.4 Mini when what matters is LMArena Vision: homework or SAGE (Vals AI), where it leads.
Which is cheaper, GPT-5.4 Mini or GPT-5.6 Luna?
GPT-5.4 Mini costs $0.75 per million input tokens and $4.50 per million output tokens; GPT-5.6 Luna costs $0.20 and $1.20. Per solved SWE-bench Verified task, GPT-5.4 Mini costs $0.70 and GPT-5.6 Luna $0.04.
Which has the bigger context window, GPT-5.4 Mini or GPT-5.6 Luna?
GPT-5.6 Luna, with 1.05M tokens against 400K.
How many benchmarks is the GPT-5.4 Mini vs GPT-5.6 Luna comparison based on?
80 benchmarks have a result for both models as of October 21, 2026. GPT-5.4 Mini's coding index rests on 1 independent benchmark and GPT-5.6 Luna's on 2. Where only one model has a result, the page says so instead of naming a winner.