Claude Sonnet 5.5 vs Inkling Small
Updated October 21, 2026. 63 benchmarks have a result for both. Coding is ranked on the Vibe Coding Index; every other board is shown as published.
Decision reading
Pick Claude Sonnet 5.5 for coding: it scores 88.9 on the Vibe Coding Index against 29.9 for Inkling Small.
Pick Inkling Small when output tokens cost 8.3x less, or when the benchmark that matters is CyberBench (Vals AI), where it leads.
- Shared results
- 63
- Claude Sonnet 5.5 only
- 32
- Inkling Small only
- 21
- 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
Claude Sonnet 5.5
Claude Sonnet 5.5 scores 88.9 against 29.9.
2 and 1 benchmarks behind the scores
Intelligence
AA Intelligence Index
Claude Sonnet 5.5
Claude Sonnet 5.5 leads, 56.0 against 25.7.
Same board, both measured
Agentic work
AA Agentic Index
No call
Only Inkling Small has a AA Agentic Index result, 23.5.
Directional only
Reasoning
GPQA Diamond
No call
Only Inkling Small has a GPQA Diamond result, 83.6%.
Directional only
Knowledge
MMLU Pro
No call
Only Inkling Small has a MMLU Pro result, 85.6%.
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
Claude Sonnet 5.5
Claude Sonnet 5.5 leads, 70.8% against 27.6%.
Same board, both measured
Long documents
Listed context window
Claude Sonnet 5.5
Claude Sonnet 5.5 takes 1M tokens against 524K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Inkling Small
Claude Sonnet 5.5 $0.0070, Inkling Small $0.0010 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only Inkling Small has the number, $0.16.
Directional only
At a glance
- Coding index
- Claude Sonnet 5.5 88.9 from 2 benchmarks, Inkling Small 29.9 from 1 benchmark.
- Widest category
- Math, 38.0 points apart on average over 6 shared benchmarks.
- Widest single gap
- ProofBench: Claude Sonnet 5.5 100.0% against Inkling Small 6.0%, 94.0 points apart on a 0 to 100 scale.
- Output price
- Claude Sonnet 5.5 $10.00 against Inkling Small $1.20 per million output tokens, 8.3x apart.
- Context window
- Claude Sonnet 5.5 takes 1M tokens, Inkling Small 524K.
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 | Inkling Small | Ties |
|---|---|---|---|---|
| Coding | 13 | 1 | ||
| Intelligence | 2 | 0 | ||
| Agentic work | 5 | 0 | ||
| Reasoning | 8 | 0 | ||
| Math | 6 | 0 | ||
| Knowledge | 6 | 0 | ||
| General | 22 | 0 | ||
| All shared boards | 62 | 1 |
CodingLike-for-likeFour of these boards feed the Vibe Coding Index131
| Benchmark | Claude Sonnet 5.5 | Inkling Small | Leader |
|---|---|---|---|
| LiveBench coding | 94.7% | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena WebDev | 1768 | 1409 | Claude Sonnet 5.5 |
| AA Coding Index | Not measured | 52.9 | Only Inkling Small measured |
| LiveCodeBench (Vals AI) | Not measured | 85.9% | Only Inkling Small measured |
| SWE-bench Verified (Vals AI) | Not measured | 82.2% | Only Inkling Small measured |
| Terminal-Bench 4 (Vals AI) | 64.1% | 0.0% | Claude Sonnet 5.5 |
| Vibe Code Bench (Vals AI) | 92.4% | 19.1% | Claude Sonnet 5.5 |
| Code migration (Vals AI) | 69.8% | 13.7% | Claude Sonnet 5.5 |
| ProgramBench (Vals AI) | 6.5% | 0.5% | Claude Sonnet 5.5 |
| IOI (Vals AI) | 83.1% | 9.3% | Claude Sonnet 5.5 |
| Terminal-Bench 2.1 (Vals AI) | 83.2% | 55.1% | Claude Sonnet 5.5 |
| SWE-bench Multimodal (Vals AI) | 58.3% | Not measured | Only Claude Sonnet 5.5 measured |
| SkillsBench (Vals AI) | Not measured | 33.6% | Only Inkling Small measured |
| CyberBench (Vals AI) | 59.6% | 64.1% | Inkling Small |
| SciCode | 61.0% | 49.7% | Claude Sonnet 5.5 |
| 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 | 1450 | Claude Sonnet 5.5 |
| LMArena Text: software and IT | 1504 | 1447 | Claude Sonnet 5.5 |
| LMArena WebDev: React | 1817 | 1399 | Claude Sonnet 5.5 |
| LMArena WebDev: HTML | 1741 | 1398 | Claude Sonnet 5.5 |
| LMArena WebDev: from an image | 1737 | 1410 | Claude Sonnet 5.5 |
| Neither model has a result on the other 15 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Claude Sonnet 5.5 | Inkling Small | Leader |
|---|---|---|---|
| AA Intelligence Index | 56.0 | 25.7 | Claude Sonnet 5.5 |
| Epoch Capabilities Index | 166.2 | 150.3 | Claude Sonnet 5.5 |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index50
| Benchmark | Claude Sonnet 5.5 | Inkling Small | Leader |
|---|---|---|---|
| AA Agentic Index | Not measured | 23.5 | Only Inkling Small measured |
| Design Arena: agents building web apps | 1303 | Not measured | Only Claude Sonnet 5.5 measured |
| Design Arena: agents building mobile apps | 1265 | Not measured | Only Claude Sonnet 5.5 measured |
| Design Arena: spreadsheets | 1245 | 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% | 41.3% | Claude Sonnet 5.5 |
| Tax Agent Bench (Vals AI) | 42.0% | 15.4% | Claude Sonnet 5.5 |
| Legal Research Bench (Vals AI) | 48.1% | 25.5% | Claude Sonnet 5.5 |
| Harvey's Legal Agent Benchmark (Vals AI) | 10.4% | 2.9% | Claude Sonnet 5.5 |
| Excel Modeling Benchmark (Vals AI) | 75.7% | 31.8% | Claude Sonnet 5.5 |
| 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 20 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index80
| Benchmark | Claude Sonnet 5.5 | Inkling Small | Leader |
|---|---|---|---|
| GPQA Diamond | Not measured | 83.6% | Only Inkling Small measured |
| 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 |
| GPQA Diamond (Artificial Analysis run) | Not measured | 89.5% | Only Inkling Small measured |
| Humanity's Last Exam (Artificial Analysis run) | 55.0% | 33.3% | Claude Sonnet 5.5 |
| GPQA Diamond (Epoch AI run) | 95.6% | 88.5% | Claude Sonnet 5.5 |
| ARC-AGI | Not measured | 84.0% | Only Inkling Small measured |
| ARC-AGI-2 | Not measured | 40.1% | Only Inkling Small measured |
| Chess puzzles | 59.0% | Not measured | Only Claude Sonnet 5.5 measured |
| Mystery game puzzles | 65.0% | 6.0% | Claude Sonnet 5.5 |
| LMArena Text: hard prompts | 1494 | 1423 | Claude Sonnet 5.5 |
| LMArena Text: expert | 1531 | 1441 | Claude Sonnet 5.5 |
| LMArena Text: hard prompts in English | 1502 | 1429 | Claude Sonnet 5.5 |
| LMArena Vision: diagrams | 1329 | 1251 | Claude Sonnet 5.5 |
| LMArena Vision: homework | 1331 | 1257 | Claude Sonnet 5.5 |
| 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 Sonnet 5.5 | Inkling Small | Leader |
|---|---|---|---|
| OTIS Mock AIME | 100.0% | 90.0% | Claude Sonnet 5.5 |
| FrontierMath, tiers 1 to 3 | 88.8% | 46.3% | Claude Sonnet 5.5 |
| FrontierMath, tier 4 | 80.5% | 17.1% | Claude Sonnet 5.5 |
| ProofBench | 100.0% | 6.0% | Claude Sonnet 5.5 |
| LMArena Text: math | 1497 | 1459 | Claude Sonnet 5.5 |
| LMArena Text: mathematical work | 1510 | 1441 | Claude Sonnet 5.5 |
| Neither model has a result on the other 7 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index60
| Benchmark | Claude Sonnet 5.5 | Inkling Small | Leader |
|---|---|---|---|
| MMLU Pro | Not measured | 85.6% | Only Inkling Small measured |
| LegalBench (Vals AI) | Not measured | 83.0% | Only Inkling Small measured |
| CorpFin (Vals AI) | Not measured | 69.6% | Only Inkling Small measured |
| TaxEval (Vals AI) | Not measured | 75.5% | Only Inkling Small measured |
| MortgageTax (Vals AI) | Not measured | 62.3% | Only Inkling Small measured |
| MedCode (Vals AI) | 52.9% | 37.9% | Claude Sonnet 5.5 |
| SimpleQA Verified | 46.5% | 19.1% | Claude Sonnet 5.5 |
| LMArena Text: science | 1483 | 1428 | Claude Sonnet 5.5 |
| LMArena Text: medicine and healthcare | 1464 | 1413 | Claude Sonnet 5.5 |
| LMArena Text: legal and government | 1483 | 1415 | Claude Sonnet 5.5 |
| LMArena Text: business and finance | 1468 | 1413 | Claude Sonnet 5.5 |
| Neither model has a result on the other 6 boards here | |||
Web designDirectional onlyPublic boards, shown as published, kept out of the index7 boards, none shared
| Benchmark | Claude Sonnet 5.5 | Inkling Small | Leader |
|---|---|---|---|
| Design Arena: websites | 1326 | Not measured | Only Claude Sonnet 5.5 measured |
| Design Arena: UI components | 1367 | 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 | 1389 | Not measured | Only Claude Sonnet 5.5 measured |
| Design Arena: 3D | 1458 | 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 | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index220
| Benchmark | Claude Sonnet 5.5 | Inkling Small | Leader |
|---|---|---|---|
| Vals Index | 70.8% | 27.6% | Claude Sonnet 5.5 |
| LiveBench data analysis | 59.5% | Not measured | Only Claude Sonnet 5.5 measured |
| Public Benefits Bench (Vals AI) | 67.2% | 59.4% | Claude Sonnet 5.5 |
| SAGE (Vals AI) | 51.8% | 32.7% | Claude Sonnet 5.5 |
| MedScribe (Vals AI) | 91.1% | 84.1% | Claude Sonnet 5.5 |
| Vals Multimodal Index | Not measured | 50.0% | Only Inkling Small measured |
| Long context reasoning (AA-LCR) | 82.7% | 75.7% | Claude Sonnet 5.5 |
| 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 | 1413 | Claude Sonnet 5.5 |
| LMArena Text: instruction following | 1492 | 1399 | Claude Sonnet 5.5 |
| LMArena Text: creative writing | 1467 | 1334 | Claude Sonnet 5.5 |
| LMArena Vision | 1287 | 1237 | Claude Sonnet 5.5 |
| LMArena Text: English | 1484 | 1421 | Claude Sonnet 5.5 |
| LMArena Text: non-English | 1456 | 1401 | Claude Sonnet 5.5 |
| LMArena Text: Chinese | 1535 | 1464 | Claude Sonnet 5.5 |
| LMArena Text: German | Not measured | 1408 | Only Inkling Small measured |
| LMArena Text: Japanese | Not measured | 1401 | Only Inkling Small measured |
| LMArena Text: Korean | Not measured | 1367 | Only Inkling Small measured |
| LMArena Text: French | 1499 | 1435 | Claude Sonnet 5.5 |
| LMArena Text: Spanish | 1451 | 1422 | Claude Sonnet 5.5 |
| LMArena Text: Russian | 1454 | 1394 | Claude Sonnet 5.5 |
| LMArena Text: Polish | Not measured | 1428 | Only Inkling Small measured |
| LMArena Text: multi-turn | 1465 | 1416 | Claude Sonnet 5.5 |
| LMArena Text: longer queries | 1495 | 1402 | Claude Sonnet 5.5 |
| LMArena Text: writing and language | 1474 | 1357 | Claude Sonnet 5.5 |
| LMArena Text: entertainment and media | 1461 | 1352 | Claude Sonnet 5.5 |
| LMArena Vision: English | 1289 | 1243 | Claude Sonnet 5.5 |
| LMArena Vision: Chinese | Not measured | 1292 | Only Inkling Small measured |
| LMArena Vision: reading text | 1297 | 1243 | Claude Sonnet 5.5 |
| LMArena Vision: humor | Not measured | 1207 | Only Inkling Small measured |
| LMArena Vision: creative writing | 1242 | 1205 | Claude Sonnet 5.5 |
| Neither model has a result on the other 13 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Claude Sonnet 5.5 | Inkling Small | 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
Inkling Small costs less
Repository review
50K input + 3K output tokens
Inkling Small costs less
Agent loop
200K input + 10K output tokens
Inkling Small 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 | Thinking Machines Inkling Small |
|---|---|---|
| Maker | Anthropic | Thinking Machines |
| Weights | No public weights listed | Open weights |
| Released | September 28, 2026 | July 30, 2026 |
| Context window | 1M | 524K |
| Input $/Mtok | $2.00 | $0.45 |
| Output $/Mtok | $10.00 | $1.20 |
| Coding index | 88.9 | 29.9 |
| Independent measurements behind it | 2 | 1 |
| Cost per solved task | Not computable | $0.16 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Claude Sonnet 5.5 better than Inkling Small for coding?
Pick Claude Sonnet 5.5 for coding: it scores 88.9 on the Vibe Coding Index against 29.9 for Inkling Small. Pick Inkling Small when output tokens cost 8.3x less, or when the benchmark that matters is CyberBench (Vals AI), where it leads.
Which is cheaper, Claude Sonnet 5.5 or Inkling Small?
Claude Sonnet 5.5 costs $2.00 per million input tokens and $10.00 per million output tokens; Inkling Small costs $0.45 and $1.20. Cost per solved task is known for Inkling Small only.
Which has the bigger context window, Claude Sonnet 5.5 or Inkling Small?
Claude Sonnet 5.5, with 1M tokens against 524K.
How many benchmarks is the Claude Sonnet 5.5 vs Inkling Small comparison based on?
63 benchmarks have a result for both models as of October 21, 2026. Claude Sonnet 5.5's coding index rests on 2 independent benchmarks and Inkling Small's on 1. Where only one model has a result, the page says so instead of naming a winner.