Claude Haiku 5.5 vs Claude Opus 4.1
Updated October 21, 2026. 21 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 Haiku 5.5 for coding: it scores 75.9 on the Vibe Coding Index against 27.2 for Claude Opus 4.1.
Claude Opus 4.1 is neither cheaper nor larger in context, and leads no benchmark both models were measured on.
- Shared results
- 21
- Claude Haiku 5.5 only
- 41
- Claude Opus 4.1 only
- 50
- 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 Haiku 5.5
Claude Haiku 5.5 scores 75.9 against 27.2.
2 and 1 benchmarks behind the scores
Intelligence
AA Intelligence Index
Claude Haiku 5.5
Claude Haiku 5.5 leads, 43.4 against 22.8.
Same board, both measured
Reasoning
GPQA Diamond
No call
Only Claude Opus 4.1 has a GPQA Diamond result, 76.3%.
Directional only
Math
AIME
No call
Only Claude Opus 4.1 has a AIME result, 78.2%.
Directional only
Knowledge
MMLU Pro
No call
Only Claude Opus 4.1 has a MMLU Pro result, 87.9%.
Directional only
Web design
Design Arena: websites
Claude Haiku 5.5
Claude Haiku 5.5 leads, 1263 against 1177.
Same board, both measured
General
Vals Index
No call
Only Claude Haiku 5.5 has a Vals Index result, 58.7%.
Directional only
Long documents
Listed context window
Claude Haiku 5.5
Claude Haiku 5.5 takes 1M tokens against 200K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Claude Haiku 5.5
Claude Haiku 5.5 $0.0003, Claude Opus 4.1 $0.052 per turn.
List prices
At a glance
- Coding index
- Claude Haiku 5.5 75.9 from 2 benchmarks, Claude Opus 4.1 27.2 from 1 benchmark.
- Widest category
- Math, 45.5 points apart on average over 3 shared benchmarks.
- Widest single gap
- FrontierMath, tiers 1 to 3: Claude Haiku 5.5 75.1% against Claude Opus 4.1 12.6%, 62.5 points apart on a 0 to 100 scale.
- Output price
- Claude Haiku 5.5 $0.50 against Claude Opus 4.1 $75.00 per million output tokens, 150.0x apart.
- Context window
- Claude Haiku 5.5 takes 1M tokens, Claude Opus 4.1 200K.
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 5.5 | Bars | Claude Opus 4.1 | Ties |
|---|---|---|---|---|
| Coding | 2 | 0 | ||
| Intelligence | 2 | 0 | ||
| Reasoning | 3 | 0 | ||
| Math | 3 | 0 | ||
| Knowledge | 1 | 0 | ||
| Web design | 6 | 0 | ||
| General | 4 | 0 | ||
| All shared boards | 21 | 0 |
CodingLike-for-likeFour of these boards feed the Vibe Coding Index20
| Benchmark | Claude Haiku 5.5 | Claude Opus 4.1 | Leader |
|---|---|---|---|
| LiveBench coding | 91.4% | Not measured | Only Claude Haiku 5.5 measured |
| LMArena WebDev | 1586 | 1390 | Claude Haiku 5.5 |
| LiveCodeBench (Vals AI) | Not measured | 66.5% | Only Claude Opus 4.1 measured |
| Terminal-Bench 4 (Vals AI) | 36.4% | Not measured | Only Claude Haiku 5.5 measured |
| Vibe Code Bench (Vals AI) | 90.4% | Not measured | Only Claude Haiku 5.5 measured |
| Code migration (Vals AI) | 44.6% | Not measured | Only Claude Haiku 5.5 measured |
| ProgramBench (Vals AI) | 2.5% | Not measured | Only Claude Haiku 5.5 measured |
| IOI (Vals AI) | 47.3% | Not measured | Only Claude Haiku 5.5 measured |
| SWE-bench Multimodal (Vals AI) | 44.0% | Not measured | Only Claude Haiku 5.5 measured |
| Vibe Code Bench 1-100 (Vals AI) | 20.4% | Not measured | Only Claude Haiku 5.5 measured |
| CyberBench (Vals AI) | 75.5% | Not measured | Only Claude Haiku 5.5 measured |
| SciCode | 55.0% | Not measured | Only Claude Haiku 5.5 measured |
| Terminal-Bench | Not measured | 38.0% | Only Claude Opus 4.1 measured |
| FrontierCode | 46.4% | Not measured | Only Claude Haiku 5.5 measured |
| FrontierSWE | 43.8% | Not measured | Only Claude Haiku 5.5 measured |
| WeirdML | Not measured | 45.9% | Only Claude Opus 4.1 measured |
| Cybench | Not measured | 42.0% | Only Claude Opus 4.1 measured |
| LMArena Text: coding | Not measured | 1479 | Only Claude Opus 4.1 measured |
| LMArena Text: software and IT | Not measured | 1456 | Only Claude Opus 4.1 measured |
| LMArena WebDev: React | 1605 | Not measured | Only Claude Haiku 5.5 measured |
| LMArena WebDev: HTML | 1569 | 1399 | Claude Haiku 5.5 |
| Neither model has a result on the other 17 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Claude Haiku 5.5 | Claude Opus 4.1 | Leader |
|---|---|---|---|
| AA Intelligence Index | 43.4 | 22.8 | Claude Haiku 5.5 |
| Epoch Capabilities Index | 159.3 | 144.1 | Claude Haiku 5.5 |
Agentic workDirectional onlyPublic boards, shown as published, kept out of the index17 boards, none shared
| Benchmark | Claude Haiku 5.5 | Claude Opus 4.1 | Leader |
|---|---|---|---|
| LiveBench research | 81.9% | Not measured | Only Claude Haiku 5.5 measured |
| LiveBench browser | 80.0% | Not measured | Only Claude Haiku 5.5 measured |
| LiveBench long agentic | 57.6% | Not measured | Only Claude Haiku 5.5 measured |
| SREBench (Vals AI) | 5.7% | Not measured | Only Claude Haiku 5.5 measured |
| Finance Agent (Vals AI) | 54.1% | Not measured | Only Claude Haiku 5.5 measured |
| Tax Agent Bench (Vals AI) | 31.9% | Not measured | Only Claude Haiku 5.5 measured |
| Legal Research Bench (Vals AI) | 43.3% | Not measured | Only Claude Haiku 5.5 measured |
| Harvey's Legal Agent Benchmark (Vals AI) | 4.2% | Not measured | Only Claude Haiku 5.5 measured |
| Excel Modeling Benchmark (Vals AI) | 59.0% | Not measured | Only Claude Haiku 5.5 measured |
| BioMysteryBench (Vals AI) | 70.4% | Not measured | Only Claude Haiku 5.5 measured |
| Terminal-Bench-Science (Vals AI) | 10.0% | Not measured | Only Claude Haiku 5.5 measured |
| Vals Science Index | 38.5% | Not measured | Only Claude Haiku 5.5 measured |
| APEX-Agents | 56.1% | Not measured | Only Claude Haiku 5.5 measured |
| METR time horizons | Not measured | 66.8% | Only Claude Opus 4.1 measured |
| GDPval | Not measured | 43.6% | Only Claude Opus 4.1 measured |
| DeepResearch Bench | Not measured | 48.3% | Only Claude Opus 4.1 measured |
| Vending-Bench 2 | $3,602 | Not measured | Only Claude Haiku 5.5 measured |
| Neither model has a result on the other 22 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index30
| Benchmark | Claude Haiku 5.5 | Claude Opus 4.1 | Leader |
|---|---|---|---|
| GPQA Diamond | Not measured | 76.3% | Only Claude Opus 4.1 measured |
| LiveBench reasoning | 82.4% | Not measured | Only Claude Haiku 5.5 measured |
| MysteryMechanism (Vals AI) | 35.1% | Not measured | Only Claude Haiku 5.5 measured |
| MMMU Pro (Vals AI) | Not measured | 77.5% | Only Claude Opus 4.1 measured |
| Humanity's Last Exam (Artificial Analysis run) | 44.4% | Not measured | Only Claude Haiku 5.5 measured |
| GPQA Diamond (Epoch AI run) | 89.6% | 77.3% | Claude Haiku 5.5 |
| ARC-AGI | 89.0% | Not measured | Only Claude Haiku 5.5 measured |
| ARC-AGI-2 | 61.3% | Not measured | Only Claude Haiku 5.5 measured |
| SimpleBench | Not measured | 60.0% | Only Claude Opus 4.1 measured |
| Chess puzzles | 55.0% | Not measured | Only Claude Haiku 5.5 measured |
| Mystery game puzzles | 30.0% | 21.0% | Claude Haiku 5.5 |
| EBR-bench | 43.8% | 7.9% | Claude Haiku 5.5 |
| VPCT | Not measured | 35.0% | Only Claude Opus 4.1 measured |
| LMArena Text: hard prompts | Not measured | 1442 | Only Claude Opus 4.1 measured |
| LMArena Text: expert | Not measured | 1438 | Only Claude Opus 4.1 measured |
| LMArena Text: hard prompts in English | Not measured | 1451 | Only Claude Opus 4.1 measured |
| Neither model has a result on the other 5 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index30
| Benchmark | Claude Haiku 5.5 | Claude Opus 4.1 | Leader |
|---|---|---|---|
| AIME | Not measured | 78.2% | Only Claude Opus 4.1 measured |
| MATH 500 (Vals AI) | Not measured | 95.4% | Only Claude Opus 4.1 measured |
| MGSM (Vals AI) | Not measured | 94.4% | Only Claude Opus 4.1 measured |
| OTIS Mock AIME | 98.9% | 68.9% | Claude Haiku 5.5 |
| FrontierMath, tiers 1 to 3 | 75.1% | 12.6% | Claude Haiku 5.5 |
| FrontierMath, tier 4 | 46.3% | 2.4% | Claude Haiku 5.5 |
| ProofBench | 89.0% | Not measured | Only Claude Haiku 5.5 measured |
| LMArena Text: math | Not measured | 1431 | Only Claude Opus 4.1 measured |
| LMArena Text: mathematical work | Not measured | 1434 | Only Claude Opus 4.1 measured |
| Neither model has a result on the other 4 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Claude Haiku 5.5 | Claude Opus 4.1 | Leader |
|---|---|---|---|
| MMLU Pro | Not measured | 87.9% | Only Claude Opus 4.1 measured |
| LegalBench (Vals AI) | Not measured | 83.5% | Only Claude Opus 4.1 measured |
| TaxEval (Vals AI) | Not measured | 73.7% | Only Claude Opus 4.1 measured |
| MortgageTax (Vals AI) | Not measured | 61.1% | Only Claude Opus 4.1 measured |
| MedQA (Vals AI) | Not measured | 93.6% | Only Claude Opus 4.1 measured |
| MedCode (Vals AI) | 51.5% | 47.2% | Claude Haiku 5.5 |
| SimpleQA Verified | 23.8% | Not measured | Only Claude Haiku 5.5 measured |
| LMArena Text: science | Not measured | 1422 | Only Claude Opus 4.1 measured |
| LMArena Text: medicine and healthcare | Not measured | 1416 | Only Claude Opus 4.1 measured |
| LMArena Text: legal and government | Not measured | 1421 | Only Claude Opus 4.1 measured |
| LMArena Text: business and finance | Not measured | 1406 | Only Claude Opus 4.1 measured |
| Neither model has a result on the other 6 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index60
| Benchmark | Claude Haiku 5.5 | Claude Opus 4.1 | Leader |
|---|---|---|---|
| Design Arena: websites | 1263 | 1177 | Claude Haiku 5.5 |
| Design Arena: UI components | 1295 | 1164 | Claude Haiku 5.5 |
| Design Arena: game dev | 1315 | 1172 | Claude Haiku 5.5 |
| Design Arena: data viz | 1292 | 1166 | Claude Haiku 5.5 |
| Design Arena: 3D | 1343 | 1153 | Claude Haiku 5.5 |
| Design Arena: all code categories | 1279 | 1171 | Claude Haiku 5.5 |
| Design Arena: SVG | Not measured | 1152 | Only Claude Opus 4.1 measured |
| Design Arena: ASCII art | Not measured | 1167 | Only Claude Opus 4.1 measured |
| LiveBench design | 83.1% | Not measured | Only Claude Haiku 5.5 measured |
GeneralLike-for-likePublic boards, shown as published, kept out of the index40
| Benchmark | Claude Haiku 5.5 | Claude Opus 4.1 | Leader |
|---|---|---|---|
| Vals Index | 58.7% | Not measured | Only Claude Haiku 5.5 measured |
| LiveBench data analysis | 53.1% | Not measured | Only Claude Haiku 5.5 measured |
| Public Benefits Bench (Vals AI) | 63.2% | Not measured | Only Claude Haiku 5.5 measured |
| SAGE (Vals AI) | 45.8% | 31.4% | Claude Haiku 5.5 |
| MedScribe (Vals AI) | 89.5% | 73.9% | Claude Haiku 5.5 |
| Long context reasoning (AA-LCR) | 82.7% | Not measured | Only Claude Haiku 5.5 measured |
| DTBench | 95.0% | 80.0% | Claude Haiku 5.5 |
| LMCA | 51.1% | 37.1% | Claude Haiku 5.5 |
| Creative writing (Lech Mazur) | Not measured | 84.7% | Only Claude Opus 4.1 measured |
| Furniture assembly | 47.5% | Not measured | Only Claude Haiku 5.5 measured |
| LMArena Text | Not measured | 1419 | Only Claude Opus 4.1 measured |
| LMArena Text: instruction following | Not measured | 1435 | Only Claude Opus 4.1 measured |
| LMArena Text: creative writing | Not measured | 1412 | Only Claude Opus 4.1 measured |
| LMArena Text: English | Not measured | 1433 | Only Claude Opus 4.1 measured |
| LMArena Text: non-English | Not measured | 1405 | Only Claude Opus 4.1 measured |
| LMArena Text: Chinese | Not measured | 1427 | Only Claude Opus 4.1 measured |
| LMArena Text: German | Not measured | 1413 | Only Claude Opus 4.1 measured |
| LMArena Text: Japanese | Not measured | 1377 | Only Claude Opus 4.1 measured |
| LMArena Text: Korean | Not measured | 1381 | Only Claude Opus 4.1 measured |
| LMArena Text: French | Not measured | 1433 | Only Claude Opus 4.1 measured |
| LMArena Text: Spanish | Not measured | 1448 | Only Claude Opus 4.1 measured |
| LMArena Text: Russian | Not measured | 1422 | Only Claude Opus 4.1 measured |
| LMArena Text: Polish | Not measured | 1413 | Only Claude Opus 4.1 measured |
| LMArena Text: multi-turn | Not measured | 1444 | Only Claude Opus 4.1 measured |
| LMArena Text: longer queries | Not measured | 1455 | Only Claude Opus 4.1 measured |
| LMArena Text: writing and language | Not measured | 1418 | Only Claude Opus 4.1 measured |
| LMArena Text: entertainment and media | Not measured | 1398 | Only Claude Opus 4.1 measured |
| Neither model has a result on the other 19 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Claude Haiku 5.5 | Claude Opus 4.1 | 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 5.5 costs less
Repository review
50K input + 3K output tokens
Claude Haiku 5.5 costs less
Agent loop
200K input + 10K output tokens
Claude Haiku 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 Haiku 5.5 | Anthropic Claude Opus 4.1 |
|---|---|---|
| Maker | Anthropic | Anthropic |
| Weights | No public weights listed | No public weights listed |
| Released | October 7, 2026 | August 5, 2025 |
| Context window | 1M | 200K |
| Input $/Mtok | $0.10 | $15.00 |
| Output $/Mtok | $0.50 | $75.00 |
| Coding index | 75.9 | 27.2 |
| Independent measurements behind it | 2 | 1 |
| Cost per solved task | Not computable | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Claude Haiku 5.5 better than Claude Opus 4.1 for coding?
Pick Claude Haiku 5.5 for coding: it scores 75.9 on the Vibe Coding Index against 27.2 for Claude Opus 4.1. Claude Opus 4.1 is neither cheaper nor larger in context, and leads no benchmark both models were measured on.
Which is cheaper, Claude Haiku 5.5 or Claude Opus 4.1?
Claude Haiku 5.5 costs $0.10 per million input tokens and $0.50 per million output tokens; Claude Opus 4.1 costs $15.00 and $75.00. Cost per solved task is known for neither of them.
Which has the bigger context window, Claude Haiku 5.5 or Claude Opus 4.1?
Claude Haiku 5.5, with 1M tokens against 200K.
How many benchmarks is the Claude Haiku 5.5 vs Claude Opus 4.1 comparison based on?
21 benchmarks have a result for both models as of October 21, 2026. Claude Haiku 5.5's coding index rests on 2 independent benchmarks and Claude Opus 4.1's on 1. Where only one model has a result, the page says so instead of naming a winner.