Claude Sonnet 5.5 vs GPT-5.2 Pro
Claude Sonnet 5.5 costs 16.8x less per output token than GPT-5.2 Pro ($10.00 vs $168.00 per million). Updated October 21, 2026; 4 benchmarks have a result for both.
vs boards won of 4 shared
Claude Sonnet 5.5 or GPT-5.2 Pro: which to pick
Only Claude Sonnet 5.5 has a coding score, 87.3 on the Vibe Coding Index; GPT-5.2 Pro has none, so the two cannot be ranked on coding.
Pick GPT-5.2 Pro for work measured by Chess puzzles, where it leads.
Model AClaude Sonnet 5.5Anthropic87.3/1005 independent benchmarksNo cost per solved taskModel BGPT-5.2 ProOpenAINot benchmarkedNo coding benchmarkNo cost per solved task
- Shared results
- 4
- Claude Sonnet 5.5 only
- 92
- GPT-5.2 Pro only
- 3
- Like-for-like categories
- 3 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 Sonnet 5.5 has a coding score, so no call is made.
One side not measured
Intelligence
AA Intelligence Index
No call
Only Claude Sonnet 5.5 has a AA Intelligence Index result, 56.0.
Directional only
Web design
Design Arena: websites
No call
Only Claude Sonnet 5.5 has a Design Arena: websites result, 1326.
Directional only
General
Vals Index
No call
Only Claude Sonnet 5.5 has a Vals Index result, 70.8%.
Directional only
Long documents
Listed context window
Claude Sonnet 5.5
Claude Sonnet 5.5 takes 1M tokens against 400K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Claude Sonnet 5.5
Claude Sonnet 5.5 $0.0070, GPT-5.2 Pro $0.105 per turn.
List prices
At a glance
- Coding index
- Claude Sonnet 5.5 87.3 from 5 benchmarks, GPT-5.2 Pro not benchmarked.
- Widest category
- Math, 24.6 points apart on average over 2 shared benchmarks.
- Widest single gap
- FrontierMath, tier 4: Claude Sonnet 5.5 80.5% against GPT-5.2 Pro 46.0%, 34.5 points apart on a 0 to 100 scale.
- Output price
- Claude Sonnet 5.5 $10.00 against GPT-5.2 Pro $168.00 per million output tokens, 16.8x apart.
- Context window
- Claude Sonnet 5.5 takes 1M tokens, GPT-5.2 Pro 400K.
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 Sonnet 5.5 | Bars | GPT-5.2 Pro | Ties |
|---|---|---|---|---|
| Intelligence | 1 | 0 | ||
| Reasoning | 0 | 1 | ||
| Math | 2 | 0 | ||
| All shared boards | 3 | 1 |
CodingDirectional onlySix of these boards feed the Vibe Coding Index20 boards, none shared
| Benchmark | Claude Sonnet 5.5 | GPT-5.2 Pro | Leader |
|---|---|---|---|
| LiveBench coding | 94.7% | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena WebDev | 1768 | Not measured | Only Claude Sonnet 5.5 measured |
| Terminal-Bench 4 (Vals AI) | 64.1% | Not measured | Only Claude Sonnet 5.5 measured |
| Vibe Code Bench (Vals AI) | 92.4% | Not measured | Only Claude Sonnet 5.5 measured |
| Code migration (Vals AI) | 69.8% | Not measured | Only Claude Sonnet 5.5 measured |
| ProgramBench (Vals AI) | 6.5% | Not measured | Only Claude Sonnet 5.5 measured |
| IOI (Vals AI) | 83.1% | Not measured | Only Claude Sonnet 5.5 measured |
| Terminal-Bench 2.1 (Vals AI) | 83.2% | Not measured | Only Claude Sonnet 5.5 measured |
| SWE-bench Multimodal (Vals AI) | 58.3% | Not measured | Only Claude Sonnet 5.5 measured |
| CyberBench (Vals AI) | 59.6% | Not measured | Only Claude Sonnet 5.5 measured |
| SciCode | 61.0% | Not measured | Only Claude Sonnet 5.5 measured |
| FrontierCode | 52.1% | Not measured | Only Claude Sonnet 5.5 measured |
| FrontierSWE | 61.9% | Not measured | Only Claude Sonnet 5.5 measured |
| ALE-Bench | 1819.1 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: coding | 1513 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: software and IT | 1504 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena WebDev: React | 1817 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena WebDev: HTML | 1741 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena WebDev: from an image | 1737 | Not measured | Only Claude Sonnet 5.5 measured |
| SciCode | 13.8% | Not measured | Only Claude Sonnet 5.5 measured |
| Neither model has a result on the other 19 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Claude Sonnet 5.5 | GPT-5.2 Pro | Leader |
|---|---|---|---|
| AA Intelligence Index | 56.0 | Not measured | Only Claude Sonnet 5.5 measured |
| Epoch Capabilities Index | 166.2 | 156.3 | Claude Sonnet 5.5 |
Agentic workDirectional onlyPublic boards, shown as published, kept out of the index18 boards, none shared
| Benchmark | Claude Sonnet 5.5 | GPT-5.2 Pro | Leader |
|---|---|---|---|
| Design Arena: agents building web apps | 1306 | Not measured | Only Claude Sonnet 5.5 measured |
| Design Arena: agents building mobile apps | 1257 | Not measured | Only Claude Sonnet 5.5 measured |
| Design Arena: spreadsheets | 1244 | Not measured | Only Claude Sonnet 5.5 measured |
| LiveBench research | 83.6% | Not measured | Only Claude Sonnet 5.5 measured |
| LiveBench browser | 84.0% | Not measured | Only Claude Sonnet 5.5 measured |
| LiveBench long agentic | 78.8% | Not measured | Only Claude Sonnet 5.5 measured |
| SREBench (Vals AI) | 30.1% | Not measured | Only Claude Sonnet 5.5 measured |
| Finance Agent (Vals AI) | 58.1% | Not measured | Only Claude Sonnet 5.5 measured |
| Tax Agent Bench (Vals AI) | 42.0% | Not measured | Only Claude Sonnet 5.5 measured |
| Legal Research Bench (Vals AI) | 48.1% | Not measured | Only Claude Sonnet 5.5 measured |
| Harvey's Legal Agent Benchmark (Vals AI) | 10.4% | Not measured | Only Claude Sonnet 5.5 measured |
| Excel Modeling Benchmark (Vals AI) | 75.7% | Not measured | Only Claude Sonnet 5.5 measured |
| BioMysteryBench (Vals AI) | 81.1% | Not measured | Only Claude Sonnet 5.5 measured |
| Terminal-Bench-Science (Vals AI) | 47.1% | Not measured | Only Claude Sonnet 5.5 measured |
| Vals Science Index | 59.1% | Not measured | Only Claude Sonnet 5.5 measured |
| APEX-Agents | 75.5% | Not measured | Only Claude Sonnet 5.5 measured |
| SpireClimb | 1.3% | Not measured | Only Claude Sonnet 5.5 measured |
| Vending-Bench 2 | $11,165 | Not measured | Only Claude Sonnet 5.5 measured |
| Neither model has a result on the other 23 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index01
| Benchmark | Claude Sonnet 5.5 | GPT-5.2 Pro | Leader |
|---|---|---|---|
| LiveBench reasoning | 91.6% | Not measured | Only Claude Sonnet 5.5 measured |
| MysteryMechanism (Vals AI) | 49.1% | Not measured | Only Claude Sonnet 5.5 measured |
| Humanity's Last Exam (Artificial Analysis run) | 55.0% | Not measured | Only Claude Sonnet 5.5 measured |
| GPQA Diamond (Epoch AI run) | 95.6% | Not measured | Only Claude Sonnet 5.5 measured |
| ARC-AGI | Not measured | 90.5% | Only GPT-5.2 Pro measured |
| ARC-AGI-2 | Not measured | 54.2% | Only GPT-5.2 Pro measured |
| SimpleBench | Not measured | 57.4% | Only GPT-5.2 Pro measured |
| Chess puzzles | 59.0% | 60.0% | GPT-5.2 Pro |
| Mystery game puzzles | 65.0% | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: hard prompts | 1494 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: expert | 1531 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: hard prompts in English | 1502 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Vision: diagrams | 1329 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Vision: homework | 1331 | Not measured | Only Claude Sonnet 5.5 measured |
| Neither model has a result on the other 8 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Claude Sonnet 5.5 | GPT-5.2 Pro | Leader |
|---|---|---|---|
| OTIS Mock AIME | 100.0% | Not measured | Only Claude Sonnet 5.5 measured |
| FrontierMath, tiers 1 to 3 | 88.8% | 74.0% | Claude Sonnet 5.5 |
| FrontierMath, tier 4 | 80.5% | 46.0% | Claude Sonnet 5.5 |
| ProofBench | 100.0% | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: math | 1497 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: mathematical work | 1510 | Not measured | Only Claude Sonnet 5.5 measured |
| Neither model has a result on the other 7 boards here | |||
KnowledgeDirectional onlyPublic boards, shown as published, kept out of the index6 boards, none shared
| Benchmark | Claude Sonnet 5.5 | GPT-5.2 Pro | Leader |
|---|---|---|---|
| MedCode (Vals AI) | 52.9% | Not measured | Only Claude Sonnet 5.5 measured |
| SimpleQA Verified | 46.5% | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: science | 1483 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: medicine and healthcare | 1464 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: legal and government | 1483 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: business and finance | 1468 | Not measured | Only Claude Sonnet 5.5 measured |
| Neither model has a result on the other 12 boards here | |||
Web designDirectional onlyPublic boards, shown as published, kept out of the index7 boards, none shared
| Benchmark | Claude Sonnet 5.5 | GPT-5.2 Pro | Leader |
|---|---|---|---|
| Design Arena: websites | 1326 | Not measured | Only Claude Sonnet 5.5 measured |
| Design Arena: UI components | 1365 | Not measured | Only Claude Sonnet 5.5 measured |
| Design Arena: game dev | 1469 | Not measured | Only Claude Sonnet 5.5 measured |
| Design Arena: data viz | 1394 | Not measured | Only Claude Sonnet 5.5 measured |
| Design Arena: 3D | 1452 | Not measured | Only Claude Sonnet 5.5 measured |
| Design Arena: all code categories | 1364 | Not measured | Only Claude Sonnet 5.5 measured |
| LiveBench design | 85.0% | Not measured | Only Claude Sonnet 5.5 measured |
| Neither model has a result on the other 2 boards here | |||
GeneralDirectional onlyPublic boards, shown as published, kept out of the index26 boards, none shared
| Benchmark | Claude Sonnet 5.5 | GPT-5.2 Pro | Leader |
|---|---|---|---|
| Vals Index | 70.8% | Not measured | Only Claude Sonnet 5.5 measured |
| LiveBench data analysis | 59.5% | Not measured | Only Claude Sonnet 5.5 measured |
| Public Benefits Bench (Vals AI) | 67.2% | Not measured | Only Claude Sonnet 5.5 measured |
| SAGE (Vals AI) | 51.8% | Not measured | Only Claude Sonnet 5.5 measured |
| MedScribe (Vals AI) | 91.1% | Not measured | Only Claude Sonnet 5.5 measured |
| Long context reasoning (AA-LCR) | 82.7% | Not measured | Only Claude Sonnet 5.5 measured |
| DTBench | 97.3% | Not measured | Only Claude Sonnet 5.5 measured |
| LMCA | 68.3% | Not measured | Only Claude Sonnet 5.5 measured |
| Furniture assembly | 75.0% | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text | 1473 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: instruction following | 1492 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: creative writing | 1467 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Vision | 1287 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: English | 1484 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: non-English | 1456 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: Chinese | 1535 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: French | 1499 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: Spanish | 1451 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: Russian | 1454 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: multi-turn | 1465 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: longer queries | 1495 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: writing and language | 1474 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: entertainment and media | 1461 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Vision: English | 1289 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Vision: reading text | 1297 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Vision: creative writing | 1242 | Not measured | Only Claude Sonnet 5.5 measured |
| Neither model has a result on the other 20 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Claude Sonnet 5.5 | GPT-5.2 Pro | 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 Sonnet 5.5$0.0070Fits in one request
GPT-5.2 Pro$0.105Fits in one request
Claude Sonnet 5.5 costs less
Repository review
50K input + 3K output tokens
Claude Sonnet 5.5$0.130Fits in one request
GPT-5.2 Pro$1.55Fits in one request
Claude Sonnet 5.5 costs less
Agent loop
200K input + 10K output tokens
Claude Sonnet 5.5$0.500Fits in one request
GPT-5.2 Pro$5.88Fits in one request
Claude Sonnet 5.5 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 Sonnet 5.5 | OpenAI GPT-5.2 Pro |
|---|---|---|
| Maker | Anthropic | OpenAI |
| Weights | No public weights listed | No public weights listed |
| Released | September 28, 2026 | December 10, 2025 |
| Context window | 1M | 400K |
| Input $/Mtok | $2.00 | $21.00 |
| Output $/Mtok | $10.00 | $168.00 |
| Coding index | 87.3 | Not benchmarked |
| Independent measurements behind it | 5 | 0 |
| Cost per solved task | Not computable | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Claude Sonnet 5.5 better than GPT-5.2 Pro for coding?
Only Claude Sonnet 5.5 has a coding score, 87.3 on the Vibe Coding Index; GPT-5.2 Pro has none, so the two cannot be ranked on coding. Pick GPT-5.2 Pro for work measured by Chess puzzles, where it leads.
Which is cheaper, Claude Sonnet 5.5 or GPT-5.2 Pro?
Claude Sonnet 5.5 costs $2.00 per million input tokens and $10.00 per million output tokens; GPT-5.2 Pro costs $21.00 and $168.00. Cost per solved task is known for neither of them.
Which has the bigger context window, Claude Sonnet 5.5 or GPT-5.2 Pro?
Claude Sonnet 5.5, with 1M tokens against 400K.
How many benchmarks is the Claude Sonnet 5.5 vs GPT-5.2 Pro comparison based on?
4 benchmarks have a result for both models as of October 21, 2026. Claude Sonnet 5.5's coding index rests on 5 independent benchmarks and GPT-5.2 Pro's on 0. Where only one model has a result, the page says so instead of naming a winner.