Claude Opus 4.1 vs GPT-6 Luna
GPT-6 Luna leads Claude Opus 4.1 on the Artificial Analysis Intelligence Index, 38.1 to 22.8, and GPT-6 Luna costs 150.0x less per output token ($0.50 vs $75.00 per million). Updated October 22, 2026; 51 benchmarks have a result for both.
Claude Opus 4.1 or GPT-6 Luna: which to pick
Only GPT-6 Luna has a coding score, 57.3 on the Vibe Coding Index; Claude Opus 4.1 has none, so the two cannot be ranked on coding.
Pick Claude Opus 4.1 for work measured by LMArena Text: coding or LMArena Text: software and IT, where it leads.
- Shared results
- 51
- Claude Opus 4.1 only
- 22
- GPT-6 Luna only
- 52
- Like-for-like categories
- 7 of 9
Only benchmarks that tested both models count toward a pick; a result only one model has is shown but not compared.
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, six public coding benchmarks
No call
Only GPT-6 Luna has a coding score, so no call is made.
One side not measured
Intelligence
AA Intelligence Index
GPT-6 Luna
GPT-6 Luna leads, 38.1 against 22.8.
Same board, both measured
Reasoning
GPQA Diamond
No call
Only Claude Opus 4.1 has a GPQA Diamond result, 76.3%.
Directional only
Math
AIME
No call
Only Claude Opus 4.1 has a AIME result, 78.2%.
Directional only
Knowledge
MMLU Pro
No call
Only Claude Opus 4.1 has a MMLU Pro result, 87.9%.
Directional only
Web design
Design Arena: websites
GPT-6 Luna
GPT-6 Luna leads, 1271 against 1176.
Same board, both measured
General
Vals Index
No call
Only GPT-6 Luna has a Vals Index result, 52.3%.
Directional only
Long documents
Listed context window
GPT-6 Luna
GPT-6 Luna takes 1.05M tokens against 200K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
GPT-6 Luna
Claude Opus 4.1 $0.052, GPT-6 Luna $0.0003 per turn.
List prices
At a glance
- Coding index
- Claude Opus 4.1 not benchmarked, GPT-6 Luna 57.3 from 5 benchmarks.
- Widest category
- Math, 31.0 points apart on average over 5 shared benchmarks.
- Widest single gap
- FrontierMath, tiers 1 to 3: Claude Opus 4.1 12.6% against GPT-6 Luna 78.9%, 66.3 points apart on a 0 to 100 scale.
- Output price
- Claude Opus 4.1 $75.00 against GPT-6 Luna $0.50 per million output tokens, 150.0x apart.
- Context window
- Claude Opus 4.1 takes 200K tokens, GPT-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 | Claude Opus 4.1 | Bars | GPT-6 Luna | Ties |
|---|---|---|---|---|
| Coding | 2 | 2 | ||
| Intelligence | 0 | 2 | ||
| Reasoning | 3 | 2 | ||
| Math | 2 | 3 | ||
| Knowledge | 5 | 1 | ||
| Web design | 1 | 7 | ||
| General | 17 | 4 | ||
| All shared boards | 30 | 21 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index22
| Benchmark | Claude Opus 4.1 | GPT-6 Luna | Leader |
|---|---|---|---|
| LiveBench coding | Not measured | 84.5% | Only GPT-6 Luna measured |
| LMArena WebDev | 1390 | 1578 | GPT-6 Luna |
| LiveCodeBench (Vals AI) | 66.5% | Not measured | Only Claude Opus 4.1 measured |
| Terminal-Bench 4 (Vals AI) | Not measured | 13.6% | Only GPT-6 Luna measured |
| Vibe Code Bench (Vals AI) | Not measured | 81.7% | Only GPT-6 Luna measured |
| Code migration (Vals AI) | Not measured | 42.5% | Only GPT-6 Luna measured |
| ProgramBench (Vals AI) | Not measured | 0.5% | Only GPT-6 Luna measured |
| IOI (Vals AI) | Not measured | 55.6% | Only GPT-6 Luna measured |
| Terminal-Bench 2.1 (Vals AI) | Not measured | 73.0% | Only GPT-6 Luna measured |
| SWE-bench Multimodal (Vals AI) | Not measured | 37.5% | Only GPT-6 Luna measured |
| CyberBench (Vals AI) | Not measured | 76.3% | Only GPT-6 Luna measured |
| SciCode | Not measured | 54.6% | Only GPT-6 Luna measured |
| Terminal-Bench | 38.0% | Not measured | Only Claude Opus 4.1 measured |
| FrontierCode | Not measured | 42.4% | Only GPT-6 Luna measured |
| WeirdML | 45.9% | Not measured | Only Claude Opus 4.1 measured |
| Cybench | 42.0% | Not measured | Only Claude Opus 4.1 measured |
| ALE-Bench | Not measured | 1576.9 | Only GPT-6 Luna measured |
| LMArena Text: coding | 1479 | 1437 | Claude Opus 4.1 |
| LMArena Text: software and IT | 1456 | 1423 | Claude Opus 4.1 |
| LMArena WebDev: React | Not measured | 1573 | Only GPT-6 Luna measured |
| LMArena WebDev: HTML | 1399 | 1595 | GPT-6 Luna |
| LMArena WebDev: from an image | Not measured | 1571 | Only GPT-6 Luna measured |
| SciCode | 4.6% | Not measured | Only Claude Opus 4.1 measured |
| Neither model has a result on the other 16 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index02
| Benchmark | Claude Opus 4.1 | GPT-6 Luna | Leader |
|---|---|---|---|
| AA Intelligence Index | 22.8 | 38.1 | GPT-6 Luna |
| Epoch Capabilities Index | 144.1 | 156.8 | GPT-6 Luna |
Agentic workDirectional onlyPublic boards, shown as published, kept out of the index20 boards, none shared
| Benchmark | Claude Opus 4.1 | GPT-6 Luna | Leader |
|---|---|---|---|
| Design Arena: agents building web apps | Not measured | 1191 | Only GPT-6 Luna measured |
| Design Arena: agents building full-stack apps | Not measured | 1158 | Only GPT-6 Luna measured |
| Design Arena: agents building mobile apps | Not measured | 1134 | Only GPT-6 Luna measured |
| LiveBench research | Not measured | 43.5% | Only GPT-6 Luna measured |
| LiveBench browser | Not measured | 72.0% | Only GPT-6 Luna measured |
| LiveBench long agentic | Not measured | 48.1% | Only GPT-6 Luna measured |
| SREBench (Vals AI) | Not measured | 2.7% | Only GPT-6 Luna measured |
| Finance Agent (Vals AI) | Not measured | 49.9% | Only GPT-6 Luna measured |
| Tax Agent Bench (Vals AI) | Not measured | 19.9% | Only GPT-6 Luna measured |
| Legal Research Bench (Vals AI) | Not measured | 30.3% | Only GPT-6 Luna measured |
| Harvey's Legal Agent Benchmark (Vals AI) | Not measured | 4.2% | Only GPT-6 Luna measured |
| Excel Modeling Benchmark (Vals AI) | Not measured | 68.5% | Only GPT-6 Luna measured |
| BioMysteryBench (Vals AI) | Not measured | 61.5% | Only GPT-6 Luna measured |
| Terminal-Bench-Science (Vals AI) | Not measured | 4.3% | Only GPT-6 Luna measured |
| Vals Science Index | Not measured | 28.4% | Only GPT-6 Luna measured |
| APEX-Agents | Not measured | 44.3% | Only GPT-6 Luna measured |
| METR time horizons | 66.8% | Not measured | Only Claude Opus 4.1 measured |
| GDPval | 43.6% | Not measured | Only Claude Opus 4.1 measured |
| DeepResearch Bench | 48.3% | Not measured | Only Claude Opus 4.1 measured |
| SpireClimb | Not measured | 0.0% | Only GPT-6 Luna measured |
| Neither model has a result on the other 21 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index32
| Benchmark | Claude Opus 4.1 | GPT-6 Luna | Leader |
|---|---|---|---|
| GPQA Diamond | 76.3% | Not measured | Only Claude Opus 4.1 measured |
| LiveBench reasoning | Not measured | 81.8% | Only GPT-6 Luna measured |
| MysteryMechanism (Vals AI) | Not measured | 19.4% | Only GPT-6 Luna measured |
| MMMU Pro (Vals AI) | 77.5% | Not measured | Only Claude Opus 4.1 measured |
| Humanity's Last Exam (Artificial Analysis run) | Not measured | 38.5% | Only GPT-6 Luna measured |
| GPQA Diamond (Epoch AI run) | 77.3% | 90.5% | GPT-6 Luna |
| ARC-AGI | Not measured | 86.7% | Only GPT-6 Luna measured |
| ARC-AGI-2 | Not measured | 59.3% | Only GPT-6 Luna measured |
| SimpleBench | 60.0% | Not measured | Only Claude Opus 4.1 measured |
| Chess puzzles | Not measured | 36.0% | Only GPT-6 Luna measured |
| Mystery game puzzles | 21.0% | 7.0% | Claude Opus 4.1 |
| EBR-bench | 7.9% | Not measured | Only Claude Opus 4.1 measured |
| VPCT | 35.0% | Not measured | Only Claude Opus 4.1 measured |
| LMArena Text: hard prompts | 1442 | 1410 | Claude Opus 4.1 |
| LMArena Text: expert | 1438 | 1442 | GPT-6 Luna |
| LMArena Text: hard prompts in English | 1451 | 1410 | Claude Opus 4.1 |
| LMArena Vision: diagrams | Not measured | 1245 | Only GPT-6 Luna measured |
| LMArena Vision: homework | Not measured | 1261 | Only GPT-6 Luna measured |
| Neither model has a result on the other 4 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index23
| Benchmark | Claude Opus 4.1 | GPT-6 Luna | Leader |
|---|---|---|---|
| AIME | 78.2% | Not measured | Only Claude Opus 4.1 measured |
| MATH 500 (Vals AI) | 95.4% | Not measured | Only Claude Opus 4.1 measured |
| MGSM (Vals AI) | 94.4% | Not measured | Only Claude Opus 4.1 measured |
| OTIS Mock AIME | 68.9% | 98.9% | GPT-6 Luna |
| FrontierMath, tiers 1 to 3 | 12.6% | 78.9% | GPT-6 Luna |
| FrontierMath, tier 4 | 2.4% | 56.1% | GPT-6 Luna |
| ProofBench | Not measured | 64.0% | Only GPT-6 Luna measured |
| LMArena Text: math | 1431 | 1409 | Claude Opus 4.1 |
| LMArena Text: mathematical work | 1434 | 1427 | Claude Opus 4.1 |
| Neither model has a result on the other 4 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index51
| Benchmark | Claude Opus 4.1 | GPT-6 Luna | Leader |
|---|---|---|---|
| MMLU Pro | 87.9% | Not measured | Only Claude Opus 4.1 measured |
| LegalBench (Vals AI) | 83.5% | Not measured | Only Claude Opus 4.1 measured |
| TaxEval (Vals AI) | 73.7% | Not measured | Only Claude Opus 4.1 measured |
| MortgageTax (Vals AI) | 61.1% | Not measured | Only Claude Opus 4.1 measured |
| MedQA (Vals AI) | 93.6% | Not measured | Only Claude Opus 4.1 measured |
| MedCode (Vals AI) | 47.2% | 44.7% | Claude Opus 4.1 |
| SimpleQA Verified | Not measured | 41.4% | Only GPT-6 Luna measured |
| LMArena Text: science | 1422 | 1386 | Claude Opus 4.1 |
| LMArena Text: medicine and healthcare | 1416 | 1352 | Claude Opus 4.1 |
| LMArena Text: legal and government | 1421 | 1400 | Claude Opus 4.1 |
| LMArena Text: business and finance | 1406 | 1388 | Claude Opus 4.1 |
| FACTS Benchmark Suite | 40.4% | 63.3% | GPT-6 Luna |
| Neither model has a result on the other 6 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index17
| Benchmark | Claude Opus 4.1 | GPT-6 Luna | Leader |
|---|---|---|---|
| Design Arena: websites | 1176 | 1271 | GPT-6 Luna |
| Design Arena: UI components | 1162 | 1295 | GPT-6 Luna |
| Design Arena: game dev | 1171 | 1257 | GPT-6 Luna |
| Design Arena: data viz | 1166 | 1216 | GPT-6 Luna |
| Design Arena: 3D | 1152 | 1218 | GPT-6 Luna |
| Design Arena: all code categories | 1170 | 1270 | GPT-6 Luna |
| Design Arena: SVG | 1152 | 1252 | GPT-6 Luna |
| Design Arena: ASCII art | 1167 | 1153 | Claude Opus 4.1 |
| LiveBench design | Not measured | 82.5% | Only GPT-6 Luna measured |
GeneralLike-for-likePublic boards, shown as published, kept out of the index174
| Benchmark | Claude Opus 4.1 | GPT-6 Luna | Leader |
|---|---|---|---|
| Vals Index | Not measured | 52.3% | Only GPT-6 Luna measured |
| LiveBench data analysis | Not measured | 73.4% | Only GPT-6 Luna measured |
| Public Benefits Bench (Vals AI) | Not measured | 57.6% | Only GPT-6 Luna measured |
| SAGE (Vals AI) | 31.4% | 48.1% | GPT-6 Luna |
| MedScribe (Vals AI) | 73.9% | 83.7% | GPT-6 Luna |
| Long context reasoning (AA-LCR) | Not measured | 83.3% | Only GPT-6 Luna measured |
| DTBench | 80.0% | 90.1% | GPT-6 Luna |
| LMCA | 37.1% | 44.5% | GPT-6 Luna |
| Creative writing (Lech Mazur) | 84.7% | Not measured | Only Claude Opus 4.1 measured |
| Furniture assembly | Not measured | 44.2% | Only GPT-6 Luna measured |
| LMArena Text | 1419 | 1389 | Claude Opus 4.1 |
| LMArena Text: instruction following | 1435 | 1408 | Claude Opus 4.1 |
| LMArena Text: creative writing | 1412 | 1363 | Claude Opus 4.1 |
| LMArena Vision | Not measured | 1216 | Only GPT-6 Luna measured |
| LMArena Text: English | 1433 | 1393 | Claude Opus 4.1 |
| LMArena Text: non-English | 1405 | 1381 | Claude Opus 4.1 |
| LMArena Text: Chinese | 1427 | 1427 | Claude Opus 4.1 |
| LMArena Text: German | 1413 | 1376 | Claude Opus 4.1 |
| LMArena Text: Japanese | 1377 | 1369 | Claude Opus 4.1 |
| LMArena Text: Korean | 1381 | 1359 | Claude Opus 4.1 |
| LMArena Text: French | 1433 | 1408 | Claude Opus 4.1 |
| LMArena Text: Spanish | 1448 | 1391 | Claude Opus 4.1 |
| LMArena Text: Russian | 1422 | 1392 | Claude Opus 4.1 |
| LMArena Text: Polish | 1413 | 1383 | Claude Opus 4.1 |
| LMArena Text: multi-turn | 1444 | 1392 | Claude Opus 4.1 |
| LMArena Text: longer queries | 1455 | 1408 | Claude Opus 4.1 |
| LMArena Text: writing and language | 1418 | 1384 | Claude Opus 4.1 |
| LMArena Text: entertainment and media | 1398 | 1364 | Claude Opus 4.1 |
| LMArena Vision: English | Not measured | 1204 | Only GPT-6 Luna measured |
| LMArena Vision: Chinese | Not measured | 1266 | Only GPT-6 Luna measured |
| LMArena Vision: reading text | Not measured | 1225 | Only GPT-6 Luna measured |
| LMArena Vision: creative writing | Not measured | 1205 | Only GPT-6 Luna measured |
| Neither model has a result on the other 14 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Claude Opus 4.1 | GPT-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-6 Luna costs less
Repository review
50K input + 3K output tokens
GPT-6 Luna costs less
Agent loop
200K input + 10K output tokens
GPT-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 | Anthropic Claude Opus 4.1 | OpenAI GPT-6 Luna |
|---|---|---|
| Maker | Anthropic | OpenAI |
| Weights | No public weights listed | No public weights listed |
| Released | August 5, 2025 | September 22, 2026 |
| Context window | 200K | 1.05M |
| Input $/Mtok | $15.00 | $0.10 |
| Output $/Mtok | $75.00 | $0.50 |
| Coding index | Not benchmarked | 57.3 |
| Independent measurements behind it | 1 | 5 |
| Cost per solved task | Not computable | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Claude Opus 4.1 better than GPT-6 Luna for coding?
Only GPT-6 Luna has a coding score, 57.3 on the Vibe Coding Index; Claude Opus 4.1 has none, so the two cannot be ranked on coding. Pick Claude Opus 4.1 for work measured by LMArena Text: coding or LMArena Text: software and IT, where it leads.
Which is cheaper, Claude Opus 4.1 or GPT-6 Luna?
Claude Opus 4.1 costs $15.00 per million input tokens and $75.00 per million output tokens; GPT-6 Luna costs $0.10 and $0.50. Cost per solved task is known for neither of them.
Which has the bigger context window, Claude Opus 4.1 or GPT-6 Luna?
GPT-6 Luna, with 1.05M tokens against 200K.
How many benchmarks is the Claude Opus 4.1 vs GPT-6 Luna comparison based on?
51 benchmarks have a result for both models as of October 22, 2026. Claude Opus 4.1's coding index rests on 1 independent benchmark and GPT-6 Luna's on 5. Where only one model has a result, the page says so instead of naming a winner.