Claude Opus 4.5 vs o1
Claude Opus 4.5 leads o1 on the Artificial Analysis Intelligence Index, 29.1 to 15.2, and Claude Opus 4.5 costs 2.4x less per output token ($25.00 vs $60.00 per million). Updated October 21, 2026; 59 benchmarks have a result for both.
Claude Opus 4.5 or o1: which to pick
Only Claude Opus 4.5 has a coding score, 44.0 on the Vibe Coding Index; o1 has none, so the two cannot be ranked on coding.
Pick o1 for work measured by MedQA (Vals AI) or GeoBench, where it leads.
- Shared results
- 59
- Claude Opus 4.5 only
- 49
- o1 only
- 10
- 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 Claude Opus 4.5 has a coding score, so no call is made.
One side not measured
Intelligence
AA Intelligence Index
Claude Opus 4.5
Claude Opus 4.5 leads, 29.1 against 15.2.
Same board, both measured
Reasoning
GPQA Diamond
Claude Opus 4.5
Claude Opus 4.5 leads, 85.9% against 73.2%.
Same board, both measured
Math
AIME
Claude Opus 4.5
Claude Opus 4.5 leads, 95.4% against 71.5%.
Same board, both measured
Knowledge
MMLU Pro
Claude Opus 4.5
Claude Opus 4.5 leads, 87.3% against 83.5%.
Same board, both measured
Web design
Design Arena: websites
No call
Only Claude Opus 4.5 has a Design Arena: websites result, 1247.
Directional only
Long documents
Listed context window
No call
Both take 200K tokens.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Claude Opus 4.5
Claude Opus 4.5 $0.018, o1 $0.045 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only Claude Opus 4.5 has the number, $1.37.
Directional only
At a glance
- Coding index
- Claude Opus 4.5 44.0 from 3 benchmarks, o1 not benchmarked.
- Widest category
- Agentic work, 25.4 points apart on average over 2 shared benchmarks.
- Widest single gap
- ARC-AGI: Claude Opus 4.5 80.0% against o1 30.7%, 49.3 points apart on a 0 to 100 scale.
- Output price
- Claude Opus 4.5 $25.00 against o1 $60.00 per million output tokens, 2.4x apart.
- Context window
- Both take 200K tokens.
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 4.5 | Bars | o1 | Ties |
|---|---|---|---|---|
| Coding | 6 | 0 | ||
| Intelligence | 2 | 0 | ||
| Agentic work | 2 | 0 | ||
| Reasoning | 12 | 0 | ||
| Math | 6 | 0 | ||
| Knowledge | 9 | 2 | ||
| General | 19 | 1 | ||
| All shared boards | 56 | 3 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index60
| Benchmark | Claude Opus 4.5 | o1 | Leader |
|---|---|---|---|
| Aider polyglot | Not measured | 61.7% | Only o1 measured |
| SWE-bench Verified | 79.2% | Not measured | Only Claude Opus 4.5 measured |
| SWE-bench (full test set) | 52.6% | Not measured | Only Claude Opus 4.5 measured |
| SWE-bench Multilingual | 70.7% | Not measured | Only Claude Opus 4.5 measured |
| LMArena WebDev | 1494 | Not measured | Only Claude Opus 4.5 measured |
| AA Coding Index | Not measured | 39.7 | Only o1 measured |
| LiveCodeBench (Vals AI) | 83.7% | 50.3% | Claude Opus 4.5 |
| SWE-bench Verified (Vals AI) | 76.4% | Not measured | Only Claude Opus 4.5 measured |
| Vibe Code Bench (Vals AI) | 20.6% | Not measured | Only Claude Opus 4.5 measured |
| LiveCodeBench (Artificial Analysis run) | 87.1% | 67.9% | Claude Opus 4.5 |
| Terminal-Bench Hard (Artificial Analysis run) | 47.0% | 12.9% | Claude Opus 4.5 |
| Terminal-Bench | 63.1% | Not measured | Only Claude Opus 4.5 measured |
| GSO-Bench | 26.5% | Not measured | Only Claude Opus 4.5 measured |
| WeirdML | 63.7% | 46.1% | Claude Opus 4.5 |
| Cybench | 82.0% | Not measured | Only Claude Opus 4.5 measured |
| LMArena Text: coding | 1503 | 1367 | Claude Opus 4.5 |
| LMArena Text: software and IT | 1483 | 1366 | Claude Opus 4.5 |
| LMArena WebDev: React | 1478 | Not measured | Only Claude Opus 4.5 measured |
| LMArena WebDev: HTML | 1510 | Not measured | Only Claude Opus 4.5 measured |
| SciCode | Not measured | 4.6% | Only o1 measured |
| Neither model has a result on the other 19 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Claude Opus 4.5 | o1 | Leader |
|---|---|---|---|
| AA Intelligence Index | 29.1 | 15.2 | Claude Opus 4.5 |
| Epoch Capabilities Index | 150.1 | 141.7 | Claude Opus 4.5 |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Claude Opus 4.5 | o1 | Leader |
|---|---|---|---|
| Design Arena: agents building web apps | 1159 | Not measured | Only Claude Opus 4.5 measured |
| Design Arena: agents building full-stack apps | 1156 | Not measured | Only Claude Opus 4.5 measured |
| Design Arena: agents building mobile apps | 1189 | Not measured | Only Claude Opus 4.5 measured |
| Design Arena: agents building Android apps | 1175 | Not measured | Only Claude Opus 4.5 measured |
| τ²-Bench Telecom | 89.5% | 62.6% | Claude Opus 4.5 |
| METR time horizons | 75.0% | 51.1% | Claude Opus 4.5 |
| Remote Labor Index | 3.8% | Not measured | Only Claude Opus 4.5 measured |
| GDPval | 45.5% | Not measured | Only Claude Opus 4.5 measured |
| BALROG | 43.5% | Not measured | Only Claude Opus 4.5 measured |
| DeepResearch Bench | 54.8% | Not measured | Only Claude Opus 4.5 measured |
| OSWorld | 66.3% | Not measured | Only Claude Opus 4.5 measured |
| Vending-Bench 2 | $4,967 | Not measured | Only Claude Opus 4.5 measured |
| Berkeley Function Calling Leaderboard (BFCL) | 77.5% | Not measured | Only Claude Opus 4.5 measured |
| Neither model has a result on the other 28 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index120
| Benchmark | Claude Opus 4.5 | o1 | Leader |
|---|---|---|---|
| GPQA Diamond | 85.9% | 73.2% | Claude Opus 4.5 |
| MMMU Pro (Vals AI) | 83.0% | 77.4% | Claude Opus 4.5 |
| GPQA Diamond (Artificial Analysis run) | 86.6% | 74.7% | Claude Opus 4.5 |
| Humanity's Last Exam (Artificial Analysis run) | 30.1% | 7.0% | Claude Opus 4.5 |
| GPQA Diamond (Epoch AI run) | 86.0% | 76.8% | Claude Opus 4.5 |
| ARC-AGI | 80.0% | 30.7% | Claude Opus 4.5 |
| ARC-AGI-2 | 37.6% | Not measured | Only Claude Opus 4.5 measured |
| SimpleBench | 62.0% | 40.1% | Claude Opus 4.5 |
| Chess puzzles | 14.0% | 10.0% | Claude Opus 4.5 |
| Mystery game puzzles | 22.0% | Not measured | Only Claude Opus 4.5 measured |
| EBR-bench | 14.3% | Not measured | Only Claude Opus 4.5 measured |
| VPCT | 40.0% | 37.0% | Claude Opus 4.5 |
| LMArena Text: hard prompts | 1476 | 1371 | Claude Opus 4.5 |
| LMArena Text: expert | 1487 | 1361 | Claude Opus 4.5 |
| LMArena Text: hard prompts in English | 1482 | 1372 | Claude Opus 4.5 |
| Kagi LLM Benchmark | 80.2% | Not measured | Only Claude Opus 4.5 measured |
| Neither model has a result on the other 6 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index60
| Benchmark | Claude Opus 4.5 | o1 | Leader |
|---|---|---|---|
| AIME | 95.4% | 71.5% | Claude Opus 4.5 |
| MATH 500 (Vals AI) | Not measured | 90.4% | Only o1 measured |
| MGSM (Vals AI) | 95.2% | 89.3% | Claude Opus 4.5 |
| AA Math Index | 91.3 | Not measured | Only Claude Opus 4.5 measured |
| AIME 2025 (Artificial Analysis run) | 91.3% | Not measured | Only Claude Opus 4.5 measured |
| OTIS Mock AIME | 86.1% | 73.3% | Claude Opus 4.5 |
| FrontierMath, tiers 1 to 3 | 34.4% | 14.7% | Claude Opus 4.5 |
| FrontierMath, tier 4 | 4.9% | Not measured | Only Claude Opus 4.5 measured |
| ProofBench | 36.0% | Not measured | Only Claude Opus 4.5 measured |
| MATH level 5 | Not measured | 94.7% | Only o1 measured |
| LMArena Text: math | 1463 | 1388 | Claude Opus 4.5 |
| LMArena Text: mathematical work | 1468 | 1390 | Claude Opus 4.5 |
| Neither model has a result on the other 1 board here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index92
| Benchmark | Claude Opus 4.5 | o1 | Leader |
|---|---|---|---|
| MMLU Pro | 87.3% | 83.5% | Claude Opus 4.5 |
| LegalBench (Vals AI) | 84.6% | 80.4% | Claude Opus 4.5 |
| CaseLaw (Vals AI) | 62.6% | Not measured | Only Claude Opus 4.5 measured |
| CorpFin (Vals AI) | 65.1% | Not measured | Only Claude Opus 4.5 measured |
| TaxEval (Vals AI) | 74.9% | 74.3% | Claude Opus 4.5 |
| MortgageTax (Vals AI) | 68.7% | Not measured | Only Claude Opus 4.5 measured |
| MedQA (Vals AI) | 95.9% | 96.5% | o1 |
| MedCode (Vals AI) | 49.2% | Not measured | Only Claude Opus 4.5 measured |
| MMLU Pro (Artificial Analysis run) | 89.5% | 84.1% | Claude Opus 4.5 |
| SimpleQA Verified | 45.7% | 41.1% | Claude Opus 4.5 |
| GeoBench | 75.0% | 80.0% | o1 |
| LMArena Text: science | 1454 | 1369 | Claude Opus 4.5 |
| LMArena Text: medicine and healthcare | 1444 | 1355 | Claude Opus 4.5 |
| LMArena Text: legal and government | 1459 | 1368 | Claude Opus 4.5 |
| LMArena Text: business and finance | 1448 | 1328 | Claude Opus 4.5 |
| FACTS Benchmark Suite | 43.9% | Not measured | Only Claude Opus 4.5 measured |
| Neither model has a result on the other 2 boards here | |||
Web designDirectional onlyPublic boards, shown as published, kept out of the index8 boards, none shared
| Benchmark | Claude Opus 4.5 | o1 | Leader |
|---|---|---|---|
| Design Arena: websites | 1247 | Not measured | Only Claude Opus 4.5 measured |
| Design Arena: UI components | 1238 | Not measured | Only Claude Opus 4.5 measured |
| Design Arena: game dev | 1229 | Not measured | Only Claude Opus 4.5 measured |
| Design Arena: data viz | 1243 | Not measured | Only Claude Opus 4.5 measured |
| Design Arena: 3D | 1214 | Not measured | Only Claude Opus 4.5 measured |
| Design Arena: all code categories | 1242 | Not measured | Only Claude Opus 4.5 measured |
| Design Arena: SVG | 1181 | Not measured | Only Claude Opus 4.5 measured |
| Design Arena: ASCII art | 1190 | Not measured | Only Claude Opus 4.5 measured |
| Neither model has a result on the other 1 board here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index191
| Benchmark | Claude Opus 4.5 | o1 | Leader |
|---|---|---|---|
| SAGE (Vals AI) | 52.1% | Not measured | Only Claude Opus 4.5 measured |
| MedScribe (Vals AI) | 85.3% | Not measured | Only Claude Opus 4.5 measured |
| IFBench | 58.0% | 70.3% | o1 |
| Long context reasoning (AA-LCR) | 77.3% | 65.0% | Claude Opus 4.5 |
| DTBench | 89.9% | 74.7% | Claude Opus 4.5 |
| LMCA | 44.5% | 22.3% | Claude Opus 4.5 |
| Fiction.LiveBench | Not measured | 83.3% | Only o1 measured |
| Creative writing (Lech Mazur) | Not measured | 70.2% | Only o1 measured |
| CL-bench | 21.1% | Not measured | Only Claude Opus 4.5 measured |
| Furniture assembly | 28.3% | Not measured | Only Claude Opus 4.5 measured |
| LMArena Text | 1451 | 1366 | Claude Opus 4.5 |
| LMArena Text: instruction following | 1478 | 1367 | Claude Opus 4.5 |
| LMArena Text: creative writing | 1445 | 1347 | Claude Opus 4.5 |
| LMArena Vision | Not measured | 1168 | Only o1 measured |
| LMArena Text: English | 1461 | 1372 | Claude Opus 4.5 |
| LMArena Text: non-English | 1438 | 1358 | Claude Opus 4.5 |
| LMArena Text: Chinese | 1470 | 1394 | Claude Opus 4.5 |
| LMArena Text: German | 1449 | 1337 | Claude Opus 4.5 |
| LMArena Text: Japanese | 1417 | 1346 | Claude Opus 4.5 |
| LMArena Text: Korean | 1424 | 1396 | Claude Opus 4.5 |
| LMArena Text: French | 1471 | 1344 | Claude Opus 4.5 |
| LMArena Text: Spanish | 1457 | 1345 | Claude Opus 4.5 |
| LMArena Text: Russian | 1447 | 1356 | Claude Opus 4.5 |
| LMArena Text: Polish | 1439 | Not measured | Only Claude Opus 4.5 measured |
| LMArena Text: multi-turn | 1466 | 1355 | Claude Opus 4.5 |
| LMArena Text: longer queries | 1479 | 1378 | Claude Opus 4.5 |
| LMArena Text: writing and language | 1452 | 1360 | Claude Opus 4.5 |
| LMArena Text: entertainment and media | 1434 | 1358 | Claude Opus 4.5 |
| LMArena Vision: English | Not measured | 1162 | Only o1 measured |
| LMArena Vision: Chinese | Not measured | 1235 | Only o1 measured |
| LMArena Document | 1462 | Not measured | Only Claude Opus 4.5 measured |
| Neither model has a result on the other 15 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Claude Opus 4.5 | o1 | 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
Claude Opus 4.5 costs less
Repository review
50K input + 3K output tokens
Claude Opus 4.5 costs less
Agent loop
200K input + 10K output tokens
Claude Opus 4.5 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 4.5 | OpenAI o1 |
|---|---|---|
| Maker | Anthropic | OpenAI |
| Weights | No public weights listed | No public weights listed |
| Released | November 24, 2025 | December 17, 2024 |
| Context window | 200K | 200K |
| Input $/Mtok | $5.00 | $15.00 |
| Output $/Mtok | $25.00 | $60.00 |
| Coding index | 44.0 | Not benchmarked |
| Independent measurements behind it | 3 | 0 |
| Cost per solved task | $1.37 | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Claude Opus 4.5 better than o1 for coding?
Only Claude Opus 4.5 has a coding score, 44.0 on the Vibe Coding Index; o1 has none, so the two cannot be ranked on coding. Pick o1 for work measured by MedQA (Vals AI) or GeoBench, where it leads.
Which is cheaper, Claude Opus 4.5 or o1?
Claude Opus 4.5 costs $5.00 per million input tokens and $25.00 per million output tokens; o1 costs $15.00 and $60.00. Cost per solved task is known for Claude Opus 4.5 only.
Which has the bigger context window, Claude Opus 4.5 or o1?
Neither: both take 200K tokens.
How many benchmarks is the Claude Opus 4.5 vs o1 comparison based on?
59 benchmarks have a result for both models as of October 21, 2026. Claude Opus 4.5's coding index rests on 3 independent benchmarks and o1's on 0. Where only one model has a result, the page says so instead of naming a winner.