Claude Sonnet 5.5
Anthropic · released 2026-09-28 · route claude-sonnet-5-5 · Model profile · Chess results
Results
- Score
- 8895%: 78 to 99
- Grids solved
- 37 of 42
- Blank cells filled correctly
- 99.5%
- Wrong cells / empty cells / changed a given / no grid
- 1 / 0 / 4 / 0
- Broke the rules (complete grid repeating a digit)
- 1
- Near misses (three cells or fewer wrong)
- 1
- Average stated confidence
- 96%
- Average confidence when it had not solved it
- 96%
- Sure but wrong (90% or more, unsolved)
- 5
- Calibration (Brier, lower is better)
- 0.111
- API-equivalent cost per grid
- $0.138
- API-equivalent cost per solved grid
- $0.157
- Seconds per grid
- 91
- Tokens per grid (in / out)
- 913 / 13,462
- Reasoning tokens per grid
- 13,332
- Retries for an unreadable reply
- 0
- Aborted on our side (not counted)
- 0
By tier
| Tier | Needs | Solved | Output tokens | Seconds |
|---|---|---|---|---|
| Cozy | Singles only | 5 of 6 | 5,884 | 43 |
| Gentle | Scanning | 5 of 6 | 10,288 | 71 |
| Steady | Locked candidates | 5 of 6 | 14,392 | 96 |
| Tricky | Hidden pairs and triples | 6 of 6 | 17,670 | 119 |
| Devious | Wings and fish | 4 of 6 | 8,807 | 62 |
| Expert | Deep wings and fish | 6 of 6 | 14,058 | 95 |
| Beyond | No human technique finishes it | 6 of 6 | 23,134 | 150 |
Cells by the technique they needed
Each blank cell is tagged with the simplest technique that fills it, given everything a solver could fill before it.
| Technique | Cells | Filled correctly |
|---|---|---|
| Last free cell | 432 | 98.6% |
| Scanning | 674 | 99.6% |
| Locked candidates | 274 | 100.0% |
| Hidden pairs and triples | 258 | 100.0% |
| Wings and fish | 165 | 98.2% |
| Deep wings and fish | 181 | 100.0% |
| Search | 249 | 100.0% |
Every answer
Cozy #1Solved 50 of 50 cells96% sure · 6,149 tokens · $0.065Cozy #2Changed a given digit 43 of 48 cells96% sure · 5,223 tokens · $0.056Cozy #3Solved 49 of 49 cells97% sure · 6,908 tokens · $0.073Cozy #4Solved 50 of 50 cells96% sure · 7,940 tokens · $0.083Cozy #5Solved 49 of 49 cells97% sure · 5,007 tokens · $0.054Cozy #6Solved 39 of 39 cells96% sure · 4,079 tokens · $0.044Gentle #1Solved 56 of 56 cells97% sure · 13,650 tokens · $0.140Gentle #2Changed a given digit 50 of 51 cells96% sure · 10,024 tokens · $0.104Gentle #3Solved 52 of 52 cells96% sure · 10,182 tokens · $0.105Gentle #4Solved 51 of 51 cells97% sure · 5,971 tokens · $0.063Gentle #5Solved 56 of 56 cells96% sure · 13,687 tokens · $0.141Gentle #6Solved 52 of 52 cells96% sure · 8,213 tokens · $0.086Steady #1Changed a given digit 52 of 53 cells97% sure · 9,526 tokens · $0.099Steady #2Solved 53 of 53 cells96% sure · 17,456 tokens · $0.178Steady #3Solved 49 of 49 cells96% sure · 9,012 tokens · $0.094Steady #4Solved 54 of 54 cells96% sure · 15,119 tokens · $0.155Steady #5Solved 53 of 53 cells97% sure · 11,851 tokens · $0.122Steady #6Solved 54 of 54 cells96% sure · 23,390 tokens · $0.238Tricky #1Solved 55 of 55 cells96% sure · 13,397 tokens · $0.138Tricky #2Solved 57 of 57 cells97% sure · 11,653 tokens · $0.120Tricky #3Solved 57 of 57 cells97% sure · 11,914 tokens · $0.123Tricky #4Solved 54 of 54 cells97% sure · 10,031 tokens · $0.104Tricky #5Solved 55 of 55 cells97% sure · 9,307 tokens · $0.097Tricky #6Solved 56 of 56 cells97% sure · 49,720 tokens · $0.501Devious #1Solved 55 of 55 cells96% sure · 9,835 tokens · $0.102Devious #2Wrong cells 53 of 55 cells96% sure · 8,502 tokens · $0.089Devious #3Solved 49 of 49 cells96% sure · 8,835 tokens · $0.092Devious #4Changed a given digit 37 of 40 cells96% sure · 8,022 tokens · $0.084Devious #5Solved 47 of 47 cells96% sure · 8,397 tokens · $0.088Devious #6Solved 54 of 54 cells96% sure · 9,252 tokens · $0.096Expert #1Solved 58 of 58 cells97% sure · 22,166 tokens · $0.223Expert #2Solved 53 of 53 cells96% sure · 10,296 tokens · $0.107Expert #3Solved 54 of 54 cells96% sure · 12,852 tokens · $0.132Expert #4Solved 57 of 57 cells96% sure · 16,706 tokens · $0.171Expert #5Solved 58 of 58 cells96% sure · 11,302 tokens · $0.117Expert #6Solved 54 of 54 cells96% sure · 11,023 tokens · $0.114Beyond #1Solved 60 of 60 cells97% sure · 26,396 tokens · $0.268Beyond #2Solved 57 of 57 cells97% sure · 19,087 tokens · $0.195Beyond #3Solved 56 of 56 cells97% sure · 31,352 tokens · $0.317Beyond #4Solved 57 of 57 cells97% sure · 15,752 tokens · $0.161Beyond #5Solved 59 of 59 cells96% sure · 20,492 tokens · $0.209Beyond #6Solved 57 of 57 cells96% sure · 25,722 tokens · $0.261