Claude Sonnet 5.5 vs Solar Pro 4
Claude Sonnet 5.5 leads Solar Pro 4 on the Artificial Analysis Intelligence Index, 56.0 to 28.2, and Solar Pro 4 costs 16.7x less per output token ($0.60 vs $10.00 per million). Updated October 22, 2026; 39 benchmarks have a result for both.
Claude Sonnet 5.5 or Solar Pro 4: which to pick
Only Claude Sonnet 5.5 has a coding score, 87.3 on the Vibe Coding Index; Solar Pro 4 has none, so the two cannot be ranked on coding.
Pick Solar Pro 4 for output tokens 16.7x cheaper ($0.60 vs $10.00 per million).
- Shared results
- 39
- Claude Sonnet 5.5 only
- 59
- Solar Pro 4 only
- 6
- 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
No call
Only Claude Sonnet 5.5 has a coding score, so no call is made.
One side not measured
Intelligence
AA Intelligence Index
Claude Sonnet 5.5
Claude Sonnet 5.5 leads, 56.0 against 28.2.
Same board, both measured
Web design
Design Arena: websites
Claude Sonnet 5.5
Claude Sonnet 5.5 leads, 1327 against 1176.
Same board, both measured
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 524K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Solar Pro 4
Claude Sonnet 5.5 $0.0070, Solar Pro 4 $0.0004 per turn.
List prices
At a glance
- Coding index
- Claude Sonnet 5.5 87.3 from 5 benchmarks, Solar Pro 4 not benchmarked.
- Widest category
- Coding, 32.4 points apart on average over 7 shared benchmarks.
- Widest single gap
- LMArena WebDev: Claude Sonnet 5.5 1768 against Solar Pro 4 1371, 56.8 points apart on a 0 to 100 scale.
- Output price
- Claude Sonnet 5.5 $10.00 against Solar Pro 4 $0.60 per million output tokens, 16.7x apart.
- Context window
- Claude Sonnet 5.5 takes 1M tokens, Solar Pro 4 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 | Solar Pro 4 | Ties |
|---|---|---|---|---|
| Coding | 7 | 0 | ||
| Intelligence | 1 | 0 | ||
| Agentic work | 1 | 0 | ||
| Reasoning | 4 | 0 | ||
| Math | 2 | 0 | ||
| Knowledge | 4 | 0 | ||
| Web design | 6 | 0 | ||
| General | 14 | 0 | ||
| All shared boards | 39 | 0 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index70
| Benchmark | Claude Sonnet 5.5 | Solar Pro 4 | Leader |
|---|---|---|---|
| LiveBench coding | 94.7% | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena WebDev | 1768 | 1371 | Claude Sonnet 5.5 |
| AA Coding Index | Not measured | 52.7 | Only Solar Pro 4 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% | 48.0% | 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 | 179.3 | Claude Sonnet 5.5 |
| LMArena Text: coding | 1513 | 1438 | Claude Sonnet 5.5 |
| LMArena Text: software and IT | 1504 | 1431 | Claude Sonnet 5.5 |
| LMArena WebDev: React | 1817 | 1363 | Claude Sonnet 5.5 |
| LMArena WebDev: HTML | 1741 | 1371 | Claude Sonnet 5.5 |
| 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 |
| SWE-Bench Pro V2 | 95.8% | Not measured | Only Claude Sonnet 5.5 measured |
| Neither model has a result on the other 21 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Claude Sonnet 5.5 | Solar Pro 4 | Leader |
|---|---|---|---|
| AA Intelligence Index | 56.0 | 28.2 | Claude Sonnet 5.5 |
| Epoch Capabilities Index | 166.2 | Not measured | Only Claude Sonnet 5.5 measured |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Claude Sonnet 5.5 | Solar Pro 4 | Leader |
|---|---|---|---|
| Design Arena: agents building web apps | 1305 | 1105 | Claude Sonnet 5.5 |
| Design Arena: agents building mobile apps | 1260 | Not measured | Only Claude Sonnet 5.5 measured |
| Design Arena: spreadsheets | 1271 | 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 24 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index40
| Benchmark | Claude Sonnet 5.5 | Solar Pro 4 | 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 |
| GPQA Diamond (Artificial Analysis run) | Not measured | 89.1% | Only Solar Pro 4 measured |
| Humanity's Last Exam (Artificial Analysis run) | 55.0% | 29.8% | Claude Sonnet 5.5 |
| GPQA Diamond (Epoch AI run) | 95.6% | Not measured | Only Claude Sonnet 5.5 measured |
| Chess puzzles | 59.0% | Not measured | Only Claude Sonnet 5.5 measured |
| Mystery game puzzles | 65.0% | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: hard prompts | 1494 | 1400 | Claude Sonnet 5.5 |
| LMArena Text: expert | 1531 | 1428 | Claude Sonnet 5.5 |
| LMArena Text: hard prompts in English | 1502 | 1427 | Claude Sonnet 5.5 |
| LMArena Vision: diagrams | 1329 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Vision: homework | 1331 | Not measured | Only Claude Sonnet 5.5 measured |
| Humanity's Last Exam (Scale run) | 37.5% | Not measured | Only Claude Sonnet 5.5 measured |
| Neither model has a result on the other 10 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Claude Sonnet 5.5 | Solar Pro 4 | Leader |
|---|---|---|---|
| OTIS Mock AIME | 100.0% | Not measured | Only Claude Sonnet 5.5 measured |
| FrontierMath, tiers 1 to 3 | 88.8% | Not measured | Only Claude Sonnet 5.5 measured |
| FrontierMath, tier 4 | 80.5% | Not measured | Only Claude Sonnet 5.5 measured |
| ProofBench | 100.0% | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: math | 1497 | 1421 | Claude Sonnet 5.5 |
| LMArena Text: mathematical work | 1510 | 1427 | Claude Sonnet 5.5 |
| Neither model has a result on the other 8 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index40
| Benchmark | Claude Sonnet 5.5 | Solar Pro 4 | 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 | 1404 | Claude Sonnet 5.5 |
| LMArena Text: medicine and healthcare | 1464 | 1374 | Claude Sonnet 5.5 |
| LMArena Text: legal and government | 1483 | 1383 | Claude Sonnet 5.5 |
| LMArena Text: business and finance | 1468 | 1381 | Claude Sonnet 5.5 |
| Neither model has a result on the other 14 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index60
| Benchmark | Claude Sonnet 5.5 | Solar Pro 4 | Leader |
|---|---|---|---|
| Design Arena: websites | 1327 | 1176 | Claude Sonnet 5.5 |
| Design Arena: UI components | 1369 | 1147 | Claude Sonnet 5.5 |
| Design Arena: game dev | 1472 | 1169 | Claude Sonnet 5.5 |
| Design Arena: data viz | 1382 | 1178 | Claude Sonnet 5.5 |
| Design Arena: 3D | 1442 | 1178 | Claude Sonnet 5.5 |
| Design Arena: all code categories | 1365 | 1182 | Claude Sonnet 5.5 |
| 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 index140
| Benchmark | Claude Sonnet 5.5 | Solar Pro 4 | 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% | 70.7% | 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 | 1388 | Claude Sonnet 5.5 |
| LMArena Text: instruction following | 1492 | 1375 | Claude Sonnet 5.5 |
| LMArena Text: creative writing | 1467 | 1317 | Claude Sonnet 5.5 |
| LMArena Vision | 1287 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: English | 1484 | 1414 | Claude Sonnet 5.5 |
| LMArena Text: non-English | 1456 | 1363 | Claude Sonnet 5.5 |
| LMArena Text: Chinese | 1535 | 1422 | Claude Sonnet 5.5 |
| LMArena Text: German | Not measured | 1358 | Only Solar Pro 4 measured |
| LMArena Text: Japanese | Not measured | 1320 | Only Solar Pro 4 measured |
| LMArena Text: Korean | Not measured | 1383 | Only Solar Pro 4 measured |
| LMArena Text: French | 1499 | 1400 | Claude Sonnet 5.5 |
| LMArena Text: Spanish | 1451 | 1409 | Claude Sonnet 5.5 |
| LMArena Text: Russian | 1454 | 1357 | Claude Sonnet 5.5 |
| LMArena Text: Polish | Not measured | 1304 | Only Solar Pro 4 measured |
| LMArena Text: multi-turn | 1465 | 1385 | Claude Sonnet 5.5 |
| LMArena Text: longer queries | 1495 | 1382 | Claude Sonnet 5.5 |
| LMArena Text: writing and language | 1474 | 1344 | Claude Sonnet 5.5 |
| LMArena Text: entertainment and media | 1461 | 1332 | Claude Sonnet 5.5 |
| 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 18 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Claude Sonnet 5.5 | Solar Pro 4 | 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
Solar Pro 4 costs less
Repository review
50K input + 3K output tokens
Solar Pro 4 costs less
Agent loop
200K input + 10K output tokens
Solar Pro 4 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 | Upstage Solar Pro 4 |
|---|---|---|
| Maker | Anthropic | Upstage |
| Weights | No public weights listed | No public weights listed |
| Released | September 28, 2026 | August 10, 2026 |
| Context window | 1M | 524K |
| Input $/Mtok | $2.00 | $0.15 |
| Output $/Mtok | $10.00 | $0.60 |
| Coding index | 87.3 | Not benchmarked |
| Independent measurements behind it | 5 | 1 |
| Cost per solved task | Not computable | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Claude Sonnet 5.5 better than Solar Pro 4 for coding?
Only Claude Sonnet 5.5 has a coding score, 87.3 on the Vibe Coding Index; Solar Pro 4 has none, so the two cannot be ranked on coding. Pick Solar Pro 4 for output tokens 16.7x cheaper ($0.60 vs $10.00 per million).
Which is cheaper, Claude Sonnet 5.5 or Solar Pro 4?
Claude Sonnet 5.5 costs $2.00 per million input tokens and $10.00 per million output tokens; Solar Pro 4 costs $0.15 and $0.60. Cost per solved task is known for neither of them.
Which has the bigger context window, Claude Sonnet 5.5 or Solar Pro 4?
Claude Sonnet 5.5, with 1M tokens against 524K.
How many benchmarks is the Claude Sonnet 5.5 vs Solar Pro 4 comparison based on?
39 benchmarks have a result for both models as of October 22, 2026. Claude Sonnet 5.5's coding index rests on 5 independent benchmarks and Solar Pro 4's on 1. Where only one model has a result, the page says so instead of naming a winner.