Claude Fable 5.2 vs Claude Sonnet 5.5
Claude Fable 5.2 leads Claude Sonnet 5.5 on coding, 87.8 to 84.3 on the Vibe Coding Index, and Claude Sonnet 5.5 costs 4.0x less per output token ($10.00 vs $40.00 per million). Updated November 14, 2026; 62 benchmarks have a result for both.
vs boards won of 62 shared, 1 tied
Claude Fable 5.2 or Claude Sonnet 5.5: which to pick
Pick Claude Fable 5.2 for coding: it scores 87.8 on the Vibe Coding Index against 84.3 for Claude Sonnet 5.5, though on 4 benchmarks against 5.
Pick Claude Sonnet 5.5 for output tokens 4.0x cheaper ($10.00 vs $40.00 per million) and work measured by Terminal-Bench 4.0 (Artificial Analysis run) or LMArena WebDev: HTML, where it leads.
Model AClaude Fable 5.2Anthropic87.8/1004 independent benchmarksNo cost per solved taskModel BClaude Sonnet 5.5Anthropic84.3/1005 independent benchmarksNo cost per solved task
- Shared results
- 62
- Claude Fable 5.2 only
- 6
- Claude Sonnet 5.5 only
- 59
- Like-for-like categories
- 8 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
Claude Fable 5.2
Claude Fable 5.2 scores 87.8 against 84.3.
4 and 5 benchmarks behind the scores
Intelligence
AA Intelligence Index
Claude Fable 5.2
Claude Fable 5.2 leads, 64.6 against 54.5.
Same board, both measured
Web design
Design Arena: websites
Claude Fable 5.2
Claude Fable 5.2 leads, 1351 against 1309.
Same board, both measured
General
Vals Index
Claude Fable 5.2
Claude Fable 5.2 leads, 71.3% against 70.8%.
Same board, both measured
Long documents
Listed context window
No call
Both take 1M tokens.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Claude Sonnet 5.5
Claude Fable 5.2 $0.028, Claude Sonnet 5.5 $0.0070 per turn.
List prices
At a glance
- Coding index
- Claude Fable 5.2 87.8 from 4 benchmarks, Claude Sonnet 5.5 84.3 from 5 benchmarks.
- Widest category
- Knowledge, 32.8 points apart on average over 2 shared benchmarks.
- Widest single gap
- SimpleQA Verified: Claude Fable 5.2 94.0% against Claude Sonnet 5.5 46.5%, 47.5 points apart on a 0 to 100 scale.
- Output price
- Claude Fable 5.2 $40.00 against Claude Sonnet 5.5 $10.00 per million output tokens, 4.0x apart.
- Context window
- Both take 1M 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 Fable 5.2 | Bars | Claude Sonnet 5.5 | Ties |
|---|---|---|---|---|
| Coding | 13 | 2 | ||
| Intelligence | 2 | 0 | ||
| Agentic work | 9 | 4 | ||
| Reasoning | 11 | 2 | ||
| Math | 2 | 1 | 1 tie | |
| Knowledge | 2 | 0 | ||
| Web design | 5 | 1 | ||
| General | 6 | 1 | ||
| All shared boards | 50 | 11 | 1 tie |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index132
| Benchmark | Claude Fable 5.2 | Claude Sonnet 5.5 | Leader |
|---|---|---|---|
| LiveBench coding | 79.2% | 77.2% | Claude Fable 5.2 |
| LMArena WebDev | 1838 | 1772 | Claude Fable 5.2 |
| Terminal-Bench 4 (Vals AI) | 65.2% | 64.1% | Claude Fable 5.2 |
| Vibe Code Bench (Vals AI) | 93.8% | 92.4% | Claude Fable 5.2 |
| Code migration (Vals AI) | Not measured | 69.8% | Only Claude Sonnet 5.5 measured |
| ProgramBench (Vals AI) | 19.0% | 6.5% | Claude Fable 5.2 |
| IOI (Vals AI) | Not measured | 83.1% | Only Claude Sonnet 5.5 measured |
| Terminal-Bench 2.1 (Vals AI) | Not measured | 83.2% | Only Claude Sonnet 5.5 measured |
| SWE-bench Multimodal (Vals AI) | 62.3% | 58.3% | Claude Fable 5.2 |
| CyberBench (Vals AI) | Not measured | 59.6% | Only Claude Sonnet 5.5 measured |
| SciCode | 67.7% | 61.0% | Claude Fable 5.2 |
| Terminal-Bench 4.0 (Artificial Analysis run) | 61.6% | 63.6% | Claude Sonnet 5.5 |
| FrontierCode 2.0 | 49.1% | 41.7% | Claude Fable 5.2 |
| FrontierCode | Not measured | 52.1% | Only Claude Sonnet 5.5 measured |
| FrontierSWE | 69.9% | 61.9% | Claude Fable 5.2 |
| MirrorCode | Not measured | 97.8% | Only Claude Sonnet 5.5 measured |
| ALE-Bench | 2509.8 | 1819.1 | Claude Fable 5.2 |
| LMArena Text: coding | Not measured | 1501 | Only Claude Sonnet 5.5 measured |
| LMArena Text: software and IT | Not measured | 1497 | Only Claude Sonnet 5.5 measured |
| LMArena WebDev: React | 1915 | 1822 | Claude Fable 5.2 |
| LMArena WebDev: HTML | 1738 | 1753 | Claude Sonnet 5.5 |
| LMArena WebDev: from an image | Not measured | 1744 | Only Claude Sonnet 5.5 measured |
| SciCode | Not measured | 13.8% | Only Claude Sonnet 5.5 measured |
| SWE-Bench Pro V2 | Not measured | 95.8% | Only Claude Sonnet 5.5 measured |
| GameBench 2 | 99.1 | 91.4 | Claude Fable 5.2 |
| Terminal-Bench 4.0 | Not measured | 61.8% | Only Claude Sonnet 5.5 measured |
| CursorBench 4.0 | 60.0% | 55.5% | Claude Fable 5.2 |
| Neither model has a result on the other 25 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Claude Fable 5.2 | Claude Sonnet 5.5 | Leader |
|---|---|---|---|
| AA Intelligence Index | 64.6 | 54.5 | Claude Fable 5.2 |
| Epoch Capabilities Index | 173.4 | 166.6 | Claude Fable 5.2 |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index94
| Benchmark | Claude Fable 5.2 | Claude Sonnet 5.5 | Leader |
|---|---|---|---|
| Design Arena: agents building web apps | Not measured | 1296 | Only Claude Sonnet 5.5 measured |
| Design Arena: agents building full-stack apps | 1402 | Not measured | Only Claude Fable 5.2 measured |
| Design Arena: agents building mobile apps | 1325 | 1259 | Claude Fable 5.2 |
| Design Arena: agents building Android apps | Not measured | 1250 | Only Claude Sonnet 5.5 measured |
| Design Arena: spreadsheets | 1434 | 1238 | Claude Fable 5.2 |
| LiveBench research | 94.5% | 88.0% | Claude Fable 5.2 |
| LiveBench browser | 86.9% | 89.3% | Claude Sonnet 5.5 |
| LiveBench long agentic | 82.9% | 63.4% | Claude Fable 5.2 |
| SREBench (Vals AI) | Not measured | 30.1% | Only Claude Sonnet 5.5 measured |
| Finance Agent (Vals AI) | Not measured | 58.1% | Only Claude Sonnet 5.5 measured |
| Tax Agent Bench (Vals AI) | 32.1% | 42.0% | Claude Sonnet 5.5 |
| Legal Research Bench (Vals AI) | 46.1% | 48.1% | Claude Sonnet 5.5 |
| Harvey's Legal Agent Benchmark (Vals AI) | 5.0% | 10.4% | Claude Sonnet 5.5 |
| Excel Modeling Benchmark (Vals AI) | Not measured | 75.7% | Only Claude Sonnet 5.5 measured |
| BioMysteryBench (Vals AI) | 83.7% | 81.1% | Claude Fable 5.2 |
| Terminal-Bench-Science (Vals AI) | 55.7% | 47.1% | Claude Fable 5.2 |
| Vals Science Index | 63.7% | 59.1% | Claude Fable 5.2 |
| APEX-Agents | 80.1% | 75.5% | Claude Fable 5.2 |
| Remote Labor Index | 41.3% | Not measured | Only Claude Fable 5.2 measured |
| SpireClimb | 15.5% | 1.3% | Claude Fable 5.2 |
| Vending-Bench 2 | Not measured | $11,165 | 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 index112
| Benchmark | Claude Fable 5.2 | Claude Sonnet 5.5 | Leader |
|---|---|---|---|
| LiveBench reasoning | 88.8% | 91.6% | Claude Sonnet 5.5 |
| MysteryMechanism (Vals AI) | 51.8% | 49.1% | Claude Fable 5.2 |
| Humanity's Last Exam (Artificial Analysis run) | 74.3% | 55.0% | Claude Fable 5.2 |
| HLE-Diamond (Artificial Analysis run) | 80.2% | 53.3% | Claude Fable 5.2 |
| CritPt v2, hard subset (Artificial Analysis run) | 76.5% | 59.0% | Claude Fable 5.2 |
| GPQA Diamond (Epoch AI run) | 93.9% | 95.6% | Claude Sonnet 5.5 |
| ARC-AGI | 98.5% | 96.5% | Claude Fable 5.2 |
| ARC-AGI-2 | 93.8% | 83.9% | Claude Fable 5.2 |
| SimpleBench | 94.9% | 75.9% | Claude Fable 5.2 |
| Chess puzzles | 79.0% | 59.0% | Claude Fable 5.2 |
| Mystery game puzzles | 90.0% | 65.0% | Claude Fable 5.2 |
| EBR-bench | 90.5% | Not measured | Only Claude Fable 5.2 measured |
| LMArena Text: hard prompts | Not measured | 1488 | Only Claude Sonnet 5.5 measured |
| LMArena Text: expert | Not measured | 1508 | Only Claude Sonnet 5.5 measured |
| LMArena Text: hard prompts in English | Not measured | 1494 | Only Claude Sonnet 5.5 measured |
| LMArena Vision: diagrams | Not measured | 1316 | Only Claude Sonnet 5.5 measured |
| LMArena Vision: homework | Not measured | 1322 | Only Claude Sonnet 5.5 measured |
| Humanity's Last Exam (Scale run) | 72.4% | 37.5% | Claude Fable 5.2 |
| GoBench | 2566 | 2085 | Claude Fable 5.2 |
| Neither model has a result on the other 7 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index21
| Benchmark | Claude Fable 5.2 | Claude Sonnet 5.5 | Leader |
|---|---|---|---|
| OTIS Mock AIME | 99.7% | 100.0% | Claude Sonnet 5.5 |
| FrontierMath, tiers 1 to 3 | 95.1% | 88.8% | Claude Fable 5.2 |
| FrontierMath, tier 4 | 100.0% | 80.5% | Claude Fable 5.2 |
| ProofBench | 100.0% | 100.0% | Tie |
| LMArena Text: math | Not measured | 1483 | Only Claude Sonnet 5.5 measured |
| LMArena Text: mathematical work | Not measured | 1501 | Only Claude Sonnet 5.5 measured |
| MathArena | 82.8% | Not measured | Only Claude Fable 5.2 measured |
| Neither model has a result on the other 7 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Claude Fable 5.2 | Claude Sonnet 5.5 | Leader |
|---|---|---|---|
| MedCode (Vals AI) | Not measured | 52.9% | Only Claude Sonnet 5.5 measured |
| AA-Omniscience | 66.8 | 30.5 | Claude Fable 5.2 |
| SimpleQA Verified | 94.0% | 46.5% | Claude Fable 5.2 |
| LMArena Text: science | Not measured | 1482 | Only Claude Sonnet 5.5 measured |
| LMArena Text: medicine and healthcare | Not measured | 1466 | Only Claude Sonnet 5.5 measured |
| LMArena Text: legal and government | Not measured | 1480 | Only Claude Sonnet 5.5 measured |
| LMArena Text: business and finance | Not measured | 1465 | Only Claude Sonnet 5.5 measured |
| FACTS Benchmark Suite | Not measured | 58.7% | Only Claude Sonnet 5.5 measured |
| PRBench Finance | 47.1% | Not measured | Only Claude Fable 5.2 measured |
| PRBench Legal | 49.0% | Not measured | Only Claude Fable 5.2 measured |
| Neither model has a result on the other 11 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index51
| Benchmark | Claude Fable 5.2 | Claude Sonnet 5.5 | Leader |
|---|---|---|---|
| Design Arena: websites | 1351 | 1309 | Claude Fable 5.2 |
| Design Arena: UI components | 1371 | 1389 | Claude Sonnet 5.5 |
| Design Arena: game dev | 1396 | 1387 | Claude Fable 5.2 |
| Design Arena: data viz | Not measured | 1359 | Only Claude Sonnet 5.5 measured |
| Design Arena: 3D | 1517 | 1400 | Claude Fable 5.2 |
| Design Arena: all code categories | 1373 | 1345 | Claude Fable 5.2 |
| Design Arena: SVG | Not measured | 1299 | Only Claude Sonnet 5.5 measured |
| LiveBench design | 85.1% | 81.3% | Claude Fable 5.2 |
| Neither model has a result on the other 1 board here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index61
| Benchmark | Claude Fable 5.2 | Claude Sonnet 5.5 | Leader |
|---|---|---|---|
| Vals Index | 71.3% | 70.8% | Claude Fable 5.2 |
| LiveBench data analysis | 81.5% | 59.5% | Claude Fable 5.2 |
| Public Benefits Bench (Vals AI) | Not measured | 67.2% | Only Claude Sonnet 5.5 measured |
| SAGE (Vals AI) | Not measured | 88.0% | Only Claude Sonnet 5.5 measured |
| MedScribe (Vals AI) | Not measured | 91.1% | Only Claude Sonnet 5.5 measured |
| Long context reasoning (AA-LCR) | 83.3% | 82.7% | Claude Fable 5.2 |
| GDPval-AA | 1831 | 1838 | Claude Sonnet 5.5 |
| DTBench | 99.2% | 97.3% | Claude Fable 5.2 |
| LMCA | 70.6% | 68.3% | Claude Fable 5.2 |
| Furniture assembly | 90.0% | 75.0% | Claude Fable 5.2 |
| LMArena Text | Not measured | 1469 | Only Claude Sonnet 5.5 measured |
| LMArena Text: instruction following | Not measured | 1487 | Only Claude Sonnet 5.5 measured |
| LMArena Text: creative writing | Not measured | 1466 | Only Claude Sonnet 5.5 measured |
| LMArena Vision | Not measured | 1284 | Only Claude Sonnet 5.5 measured |
| LMArena Text: English | Not measured | 1479 | Only Claude Sonnet 5.5 measured |
| LMArena Text: non-English | Not measured | 1455 | Only Claude Sonnet 5.5 measured |
| LMArena Text: Chinese | Not measured | 1533 | Only Claude Sonnet 5.5 measured |
| LMArena Text: German | Not measured | 1448 | Only Claude Sonnet 5.5 measured |
| LMArena Text: Japanese | Not measured | 1456 | Only Claude Sonnet 5.5 measured |
| LMArena Text: Korean | Not measured | 1413 | Only Claude Sonnet 5.5 measured |
| LMArena Text: French | Not measured | 1494 | Only Claude Sonnet 5.5 measured |
| LMArena Text: Spanish | Not measured | 1463 | Only Claude Sonnet 5.5 measured |
| LMArena Text: Russian | Not measured | 1460 | Only Claude Sonnet 5.5 measured |
| LMArena Text: Polish | Not measured | 1492 | Only Claude Sonnet 5.5 measured |
| LMArena Text: multi-turn | Not measured | 1462 | Only Claude Sonnet 5.5 measured |
| LMArena Text: longer queries | Not measured | 1487 | Only Claude Sonnet 5.5 measured |
| LMArena Text: writing and language | Not measured | 1470 | Only Claude Sonnet 5.5 measured |
| LMArena Text: entertainment and media | Not measured | 1454 | Only Claude Sonnet 5.5 measured |
| LMArena Vision: English | Not measured | 1282 | Only Claude Sonnet 5.5 measured |
| LMArena Vision: Chinese | Not measured | 1387 | Only Claude Sonnet 5.5 measured |
| LMArena Vision: reading text | Not measured | 1296 | Only Claude Sonnet 5.5 measured |
| LMArena Vision: humor | Not measured | 1266 | Only Claude Sonnet 5.5 measured |
| LMArena Vision: creative writing | Not measured | 1264 | Only Claude Sonnet 5.5 measured |
| Neither model has a result on the other 16 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Claude Fable 5.2 | Claude Sonnet 5.5 | 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 Fable 5.2$0.028Fits in one request
Claude Sonnet 5.5$0.0070Fits in one request
Claude Sonnet 5.5 costs less
Repository review
50K input + 3K output tokens
Claude Fable 5.2$0.520Fits in one request
Claude Sonnet 5.5$0.130Fits in one request
Claude Sonnet 5.5 costs less
Agent loop
200K input + 10K output tokens
Claude Fable 5.2$2.00Fits in one request
Claude Sonnet 5.5$0.500Fits 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 Fable 5.2 | Anthropic Claude Sonnet 5.5 |
|---|---|---|
| Maker | Anthropic | Anthropic |
| Weights | No public weights listed | No public weights listed |
| Released | November 9, 2026 | September 28, 2026 |
| Context window | 1M | 1M |
| Input $/Mtok | $8.00 | $2.00 |
| Output $/Mtok | $40.00 | $10.00 |
| Coding index | 87.8 | 84.3 |
| Independent measurements behind it | 4 | 5 |
| Cost per solved task | Not computable | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Claude Fable 5.2 better than Claude Sonnet 5.5 for coding?
Pick Claude Fable 5.2 for coding: it scores 87.8 on the Vibe Coding Index against 84.3 for Claude Sonnet 5.5, though on 4 benchmarks against 5. Pick Claude Sonnet 5.5 for output tokens 4.0x cheaper ($10.00 vs $40.00 per million) and work measured by Terminal-Bench 4.0 (Artificial Analysis run) or LMArena WebDev: HTML, where it leads.
Which is cheaper, Claude Fable 5.2 or Claude Sonnet 5.5?
Claude Fable 5.2 costs $8.00 per million input tokens and $40.00 per million output tokens; Claude Sonnet 5.5 costs $2.00 and $10.00. Cost per solved task is known for neither of them.
Which has the bigger context window, Claude Fable 5.2 or Claude Sonnet 5.5?
Neither: both take 1M tokens.
How many benchmarks is the Claude Fable 5.2 vs Claude Sonnet 5.5 comparison based on?
62 benchmarks have a result for both models as of November 14, 2026. Claude Fable 5.2's coding index rests on 4 independent benchmarks and Claude Sonnet 5.5's on 5. Where only one model has a result, the page says so instead of naming a winner.