Claude Haiku 4.5 vs Claude Sonnet 5.5
Claude Sonnet 5.5 leads Claude Haiku 4.5 on coding, 87.3 to 35.6 on the Vibe Coding Index, and Claude Haiku 4.5 costs 2.0x less per output token ($5.00 vs $10.00 per million). Updated October 22, 2026; 61 benchmarks have a result for both.
Claude Haiku 4.5 or Claude Sonnet 5.5: which to pick
Pick Claude Sonnet 5.5 for coding: it scores 87.3 on the Vibe Coding Index against 35.6 for Claude Haiku 4.5.
Pick Claude Haiku 4.5 for output tokens 2.0x cheaper ($5.00 vs $10.00 per million).
- Shared results
- 61
- Claude Haiku 4.5 only
- 34
- Claude Sonnet 5.5 only
- 35
- 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 Sonnet 5.5
Claude Sonnet 5.5 scores 87.3 against 35.6.
4 and 5 benchmarks behind the scores
Intelligence
AA Intelligence Index
Claude Sonnet 5.5
Claude Sonnet 5.5 leads, 56.0 against 16.9.
Same board, both measured
Agentic work
AA Agentic Index
No call
Only Claude Haiku 4.5 has a AA Agentic Index result, 8.0.
Directional only
Reasoning
GPQA Diamond
No call
Only Claude Haiku 4.5 has a GPQA Diamond result, 72.2%.
Directional only
Math
AIME
No call
Only Claude Haiku 4.5 has a AIME result, 82.7%.
Directional only
Knowledge
MMLU Pro
No call
Only Claude Haiku 4.5 has a MMLU Pro result, 78.7%.
Directional only
Web design
Design Arena: websites
Claude Sonnet 5.5
Claude Sonnet 5.5 leads, 1326 against 1122.
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 200K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Claude Haiku 4.5
Claude Haiku 4.5 $0.0035, Claude Sonnet 5.5 $0.0070 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only Claude Haiku 4.5 has the number, $0.56.
Directional only
At a glance
- Coding index
- Claude Haiku 4.5 35.6 from 4 benchmarks, Claude Sonnet 5.5 87.3 from 5 benchmarks.
- Widest category
- Agentic work, 46.7 points apart on average over 8 shared benchmarks.
- Widest single gap
- Vibe Code Bench (Vals AI): Claude Haiku 4.5 11.4% against Claude Sonnet 5.5 92.4%, 81.0 points apart on a 0 to 100 scale.
- Output price
- Claude Haiku 4.5 $5.00 against Claude Sonnet 5.5 $10.00 per million output tokens, 2.0x apart.
- Context window
- Claude Haiku 4.5 takes 200K tokens, Claude Sonnet 5.5 1M.
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 Haiku 4.5 | Bars | Claude Sonnet 5.5 | Ties |
|---|---|---|---|---|
| Coding | 0 | 10 | ||
| Intelligence | 0 | 2 | ||
| Agentic work | 0 | 8 | ||
| Reasoning | 0 | 6 | ||
| Math | 0 | 3 | ||
| Knowledge | 0 | 6 | ||
| Web design | 0 | 7 | ||
| General | 0 | 19 | ||
| All shared boards | 0 | 61 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index010
| Benchmark | Claude Haiku 4.5 | Claude Sonnet 5.5 | Leader |
|---|---|---|---|
| SWE-bench Verified | 66.6% | Not measured | Only Claude Haiku 4.5 measured |
| SWE-bench Multilingual | 64.7% | Not measured | Only Claude Haiku 4.5 measured |
| LiveBench coding | 48.1% | 94.7% | Claude Sonnet 5.5 |
| LMArena WebDev | 1330 | 1768 | Claude Sonnet 5.5 |
| AA Coding Index | 43.9 | Not measured | Only Claude Haiku 4.5 measured |
| LiveCodeBench (Vals AI) | 41.2% | Not measured | Only Claude Haiku 4.5 measured |
| SWE-bench Verified (Vals AI) | 66.6% | Not measured | Only Claude Haiku 4.5 measured |
| Terminal-Bench 4 (Vals AI) | Not measured | 64.1% | Only Claude Sonnet 5.5 measured |
| Vibe Code Bench (Vals AI) | 11.4% | 92.4% | Claude Sonnet 5.5 |
| Code migration (Vals AI) | 7.5% | 69.8% | Claude Sonnet 5.5 |
| ProgramBench (Vals AI) | 0.0% | 6.5% | Claude Sonnet 5.5 |
| IOI (Vals AI) | Not measured | 83.1% | Only Claude Sonnet 5.5 measured |
| Terminal-Bench 2.1 (Vals AI) | 43.8% | 83.2% | Claude Sonnet 5.5 |
| SWE-bench Multimodal (Vals AI) | Not measured | 58.3% | Only Claude Sonnet 5.5 measured |
| CyberBench (Vals AI) | Not measured | 59.6% | Only Claude Sonnet 5.5 measured |
| SciCode | Not measured | 61.0% | Only Claude Sonnet 5.5 measured |
| Terminal-Bench | 35.5% | Not measured | Only Claude Haiku 4.5 measured |
| FrontierCode | Not measured | 52.1% | Only Claude Sonnet 5.5 measured |
| FrontierSWE | Not measured | 61.9% | Only Claude Sonnet 5.5 measured |
| WeirdML | 45.4% | Not measured | Only Claude Haiku 4.5 measured |
| ALE-Bench | Not measured | 1819.1 | Only Claude Sonnet 5.5 measured |
| LMArena Text: coding | 1454 | 1513 | Claude Sonnet 5.5 |
| LMArena Text: software and IT | 1439 | 1504 | Claude Sonnet 5.5 |
| LMArena WebDev: React | 1326 | 1817 | Claude Sonnet 5.5 |
| LMArena WebDev: HTML | 1318 | 1741 | Claude Sonnet 5.5 |
| LMArena WebDev: from an image | Not measured | 1737 | Only Claude Sonnet 5.5 measured |
| SciCode | Not measured | 13.8% | Only Claude Sonnet 5.5 measured |
| Neither model has a result on the other 12 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index02
| Benchmark | Claude Haiku 4.5 | Claude Sonnet 5.5 | Leader |
|---|---|---|---|
| AA Intelligence Index | 16.9 | 56.0 | Claude Sonnet 5.5 |
| Epoch Capabilities Index | 142.2 | 166.2 | Claude Sonnet 5.5 |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index08
| Benchmark | Claude Haiku 4.5 | Claude Sonnet 5.5 | Leader |
|---|---|---|---|
| AA Agentic Index | 8.0 | Not measured | Only Claude Haiku 4.5 measured |
| Design Arena: agents building web apps | Not measured | 1305 | Only Claude Sonnet 5.5 measured |
| Design Arena: agents building mobile apps | Not measured | 1260 | Only Claude Sonnet 5.5 measured |
| Design Arena: spreadsheets | Not measured | 1260 | Only Claude Sonnet 5.5 measured |
| LiveBench research | 42.2% | 83.6% | Claude Sonnet 5.5 |
| LiveBench browser | 40.0% | 84.0% | Claude Sonnet 5.5 |
| LiveBench long agentic | 11.1% | 78.8% | Claude Sonnet 5.5 |
| SREBench (Vals AI) | Not measured | 30.1% | Only Claude Sonnet 5.5 measured |
| Finance Agent (Vals AI) | 31.0% | 58.1% | Claude Sonnet 5.5 |
| Tax Agent Bench (Vals AI) | 5.9% | 42.0% | Claude Sonnet 5.5 |
| Legal Research Bench (Vals AI) | 10.6% | 48.1% | Claude Sonnet 5.5 |
| Harvey's Legal Agent Benchmark (Vals AI) | Not measured | 10.4% | Only Claude Sonnet 5.5 measured |
| Excel Modeling Benchmark (Vals AI) | 22.7% | 75.7% | Claude Sonnet 5.5 |
| BioMysteryBench (Vals AI) | Not measured | 81.1% | Only Claude Sonnet 5.5 measured |
| Terminal-Bench-Science (Vals AI) | Not measured | 47.1% | Only Claude Sonnet 5.5 measured |
| Vals Science Index | Not measured | 59.1% | Only Claude Sonnet 5.5 measured |
| APEX-Agents | Not measured | 75.5% | Only Claude Sonnet 5.5 measured |
| BALROG | 31.2% | Not measured | Only Claude Haiku 4.5 measured |
| DeepResearch Bench | 45.5% | Not measured | Only Claude Haiku 4.5 measured |
| SpireClimb | Not measured | 1.3% | Only Claude Sonnet 5.5 measured |
| Vending-Bench 2 | $459 | $11,165 | Claude Sonnet 5.5 |
| Berkeley Function Calling Leaderboard (BFCL) | 68.7% | Not measured | Only Claude Haiku 4.5 measured |
| Neither model has a result on the other 19 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index06
| Benchmark | Claude Haiku 4.5 | Claude Sonnet 5.5 | Leader |
|---|---|---|---|
| GPQA Diamond | 72.2% | Not measured | Only Claude Haiku 4.5 measured |
| LiveBench reasoning | 61.7% | 91.6% | Claude Sonnet 5.5 |
| MysteryMechanism (Vals AI) | Not measured | 49.1% | Only Claude Sonnet 5.5 measured |
| MMMU Pro (Vals AI) | 46.1% | Not measured | Only Claude Haiku 4.5 measured |
| Humanity's Last Exam (Artificial Analysis run) | Not measured | 55.0% | Only Claude Sonnet 5.5 measured |
| GPQA Diamond (Epoch AI run) | 71.2% | 95.6% | Claude Sonnet 5.5 |
| ARC-AGI | 47.7% | Not measured | Only Claude Haiku 4.5 measured |
| ARC-AGI-2 | 4.0% | Not measured | Only Claude Haiku 4.5 measured |
| Chess puzzles | 8.0% | 59.0% | Claude Sonnet 5.5 |
| Mystery game puzzles | Not measured | 65.0% | Only Claude Sonnet 5.5 measured |
| LMArena Text: hard prompts | 1421 | 1494 | Claude Sonnet 5.5 |
| LMArena Text: expert | 1443 | 1531 | Claude Sonnet 5.5 |
| LMArena Text: hard prompts in English | 1435 | 1502 | Claude Sonnet 5.5 |
| LMArena Vision: diagrams | Not measured | 1329 | Only Claude Sonnet 5.5 measured |
| LMArena Vision: homework | Not measured | 1331 | Only Claude Sonnet 5.5 measured |
| Neither model has a result on the other 7 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index03
| Benchmark | Claude Haiku 4.5 | Claude Sonnet 5.5 | Leader |
|---|---|---|---|
| AIME | 82.7% | Not measured | Only Claude Haiku 4.5 measured |
| MGSM (Vals AI) | 92.2% | Not measured | Only Claude Haiku 4.5 measured |
| OTIS Mock AIME | 66.7% | 100.0% | Claude Sonnet 5.5 |
| FrontierMath, tiers 1 to 3 | Not measured | 88.8% | Only Claude Sonnet 5.5 measured |
| FrontierMath, tier 4 | Not measured | 80.5% | Only Claude Sonnet 5.5 measured |
| ProofBench | Not measured | 100.0% | Only Claude Sonnet 5.5 measured |
| MATH level 5 | 96.4% | Not measured | Only Claude Haiku 4.5 measured |
| LMArena Text: math | 1398 | 1497 | Claude Sonnet 5.5 |
| LMArena Text: mathematical work | 1430 | 1510 | Claude Sonnet 5.5 |
| Neither model has a result on the other 4 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index06
| Benchmark | Claude Haiku 4.5 | Claude Sonnet 5.5 | Leader |
|---|---|---|---|
| MMLU Pro | 78.7% | Not measured | Only Claude Haiku 4.5 measured |
| LegalBench (Vals AI) | 81.2% | Not measured | Only Claude Haiku 4.5 measured |
| CaseLaw (Vals AI) | 56.5% | Not measured | Only Claude Haiku 4.5 measured |
| CorpFin (Vals AI) | 60.6% | Not measured | Only Claude Haiku 4.5 measured |
| TaxEval (Vals AI) | 67.5% | Not measured | Only Claude Haiku 4.5 measured |
| MortgageTax (Vals AI) | 62.2% | Not measured | Only Claude Haiku 4.5 measured |
| MedQA (Vals AI) | 79.6% | Not measured | Only Claude Haiku 4.5 measured |
| MedCode (Vals AI) | 32.7% | 52.9% | Claude Sonnet 5.5 |
| SimpleQA Verified | 13.2% | 46.5% | Claude Sonnet 5.5 |
| LMArena Text: science | 1406 | 1483 | Claude Sonnet 5.5 |
| LMArena Text: medicine and healthcare | 1394 | 1464 | Claude Sonnet 5.5 |
| LMArena Text: legal and government | 1400 | 1483 | Claude Sonnet 5.5 |
| LMArena Text: business and finance | 1400 | 1468 | Claude Sonnet 5.5 |
| Neither model has a result on the other 5 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index07
| Benchmark | Claude Haiku 4.5 | Claude Sonnet 5.5 | Leader |
|---|---|---|---|
| Design Arena: websites | 1122 | 1326 | Claude Sonnet 5.5 |
| Design Arena: UI components | 1097 | 1368 | Claude Sonnet 5.5 |
| Design Arena: game dev | 1097 | 1471 | Claude Sonnet 5.5 |
| Design Arena: data viz | 1124 | 1392 | Claude Sonnet 5.5 |
| Design Arena: 3D | 1071 | 1445 | Claude Sonnet 5.5 |
| Design Arena: all code categories | 1114 | 1364 | Claude Sonnet 5.5 |
| Design Arena: SVG | 1025 | Not measured | Only Claude Haiku 4.5 measured |
| Design Arena: ASCII art | 1140 | Not measured | Only Claude Haiku 4.5 measured |
| LiveBench design | 59.9% | 85.0% | Claude Sonnet 5.5 |
GeneralLike-for-likePublic boards, shown as published, kept out of the index019
| Benchmark | Claude Haiku 4.5 | Claude Sonnet 5.5 | Leader |
|---|---|---|---|
| Vals Index | Not measured | 70.8% | Only Claude Sonnet 5.5 measured |
| LiveBench data analysis | 59.3% | 59.5% | Claude Sonnet 5.5 |
| Public Benefits Bench (Vals AI) | 54.3% | 67.2% | Claude Sonnet 5.5 |
| SAGE (Vals AI) | 31.8% | 51.8% | Claude Sonnet 5.5 |
| MedScribe (Vals AI) | 85.2% | 91.1% | Claude Sonnet 5.5 |
| Vals Multimodal Index | 42.9% | Not measured | Only Claude Haiku 4.5 measured |
| Long context reasoning (AA-LCR) | Not measured | 82.7% | Only Claude Sonnet 5.5 measured |
| DTBench | 73.6% | 97.3% | Claude Sonnet 5.5 |
| LMCA | 30.9% | 68.3% | Claude Sonnet 5.5 |
| Furniture assembly | Not measured | 75.0% | Only Claude Sonnet 5.5 measured |
| ExploitBench | 13.7% | Not measured | Only Claude Haiku 4.5 measured |
| LMArena Text | 1397 | 1473 | Claude Sonnet 5.5 |
| LMArena Text: instruction following | 1414 | 1492 | Claude Sonnet 5.5 |
| LMArena Text: creative writing | 1371 | 1467 | Claude Sonnet 5.5 |
| LMArena Vision | Not measured | 1287 | Only Claude Sonnet 5.5 measured |
| LMArena Text: English | 1414 | 1484 | Claude Sonnet 5.5 |
| LMArena Text: non-English | 1377 | 1456 | Claude Sonnet 5.5 |
| LMArena Text: Chinese | 1418 | 1535 | Claude Sonnet 5.5 |
| LMArena Text: German | 1374 | Not measured | Only Claude Haiku 4.5 measured |
| LMArena Text: Japanese | 1338 | Not measured | Only Claude Haiku 4.5 measured |
| LMArena Text: Korean | 1346 | Not measured | Only Claude Haiku 4.5 measured |
| LMArena Text: French | 1411 | 1499 | Claude Sonnet 5.5 |
| LMArena Text: Spanish | 1421 | 1451 | Claude Sonnet 5.5 |
| LMArena Text: Russian | 1381 | 1454 | Claude Sonnet 5.5 |
| LMArena Text: Polish | 1343 | Not measured | Only Claude Haiku 4.5 measured |
| LMArena Text: multi-turn | 1409 | 1465 | Claude Sonnet 5.5 |
| LMArena Text: longer queries | 1427 | 1495 | Claude Sonnet 5.5 |
| LMArena Text: writing and language | 1386 | 1474 | Claude Sonnet 5.5 |
| LMArena Text: entertainment and media | 1369 | 1461 | Claude Sonnet 5.5 |
| LMArena Vision: English | Not measured | 1289 | Only Claude Sonnet 5.5 measured |
| LMArena Vision: reading text | Not measured | 1297 | Only Claude Sonnet 5.5 measured |
| LMArena Vision: creative writing | Not measured | 1242 | Only Claude Sonnet 5.5 measured |
| LMArena Document | 1420 | Not measured | Only Claude Haiku 4.5 measured |
| 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 Haiku 4.5 | 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 Haiku 4.5 costs less
Repository review
50K input + 3K output tokens
Claude Haiku 4.5 costs less
Agent loop
200K input + 10K output tokens
Claude Haiku 4.5 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 Haiku 4.5 | Anthropic Claude Sonnet 5.5 |
|---|---|---|
| Maker | Anthropic | Anthropic |
| Weights | No public weights listed | No public weights listed |
| Released | October 15, 2025 | September 28, 2026 |
| Context window | 200K | 1M |
| Input $/Mtok | $1.00 | $2.00 |
| Output $/Mtok | $5.00 | $10.00 |
| Coding index | 35.6 | 87.3 |
| Independent measurements behind it | 4 | 5 |
| Cost per solved task | $0.56 | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Claude Haiku 4.5 better than Claude Sonnet 5.5 for coding?
Pick Claude Sonnet 5.5 for coding: it scores 87.3 on the Vibe Coding Index against 35.6 for Claude Haiku 4.5. Pick Claude Haiku 4.5 for output tokens 2.0x cheaper ($5.00 vs $10.00 per million).
Which is cheaper, Claude Haiku 4.5 or Claude Sonnet 5.5?
Claude Haiku 4.5 costs $1.00 per million input tokens and $5.00 per million output tokens; Claude Sonnet 5.5 costs $2.00 and $10.00. Cost per solved task is known for Claude Haiku 4.5 only.
Which has the bigger context window, Claude Haiku 4.5 or Claude Sonnet 5.5?
Claude Sonnet 5.5, with 1M tokens against 200K.
How many benchmarks is the Claude Haiku 4.5 vs Claude Sonnet 5.5 comparison based on?
61 benchmarks have a result for both models as of October 22, 2026. Claude Haiku 4.5'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.