Claude Haiku 5.5 vs Claude Opus 5
Updated October 21, 2026. 59 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 Opus 5 for coding: it scores 81.8 on the Vibe Coding Index against 75.9 for Claude Haiku 5.5.
Pick Claude Haiku 5.5 when output tokens cost 50.0x less, or when what matters is LiveBench coding or Vibe Code Bench (Vals AI), where it leads.
- Shared results
- 59
- Claude Haiku 5.5 only
- 3
- Claude Opus 5 only
- 71
- Like-for-like categories
- 8 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 Opus 5
Claude Opus 5 scores 81.8 against 75.9.
2 benchmarks behind each score
Intelligence
AA Intelligence Index
Claude Opus 5
Claude Opus 5 leads, 50.8 against 43.4.
Same board, both measured
Agentic work
AA Agentic Index
No call
Only Claude Opus 5 has a AA Agentic Index result, 56.5.
Directional only
Reasoning
GPQA Diamond
No call
Only Claude Opus 5 has a GPQA Diamond result, 93.4%.
Directional only
Knowledge
MMLU Pro
No call
Only Claude Opus 5 has a MMLU Pro result, 91.6%.
Directional only
Web design
Design Arena: websites
Claude Opus 5
Claude Opus 5 leads, 1309 against 1263.
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
No call
Both take 1M tokens.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Claude Haiku 5.5
Claude Haiku 5.5 $0.0003, Claude Opus 5 $0.018 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only Claude Opus 5 has the number, $1.33.
Directional only
At a glance
- Coding index
- Claude Haiku 5.5 75.9 from 2 benchmarks, Claude Opus 5 81.8 from 2 benchmarks.
- Widest category
- Knowledge, 24.1 points apart on average over 2 shared benchmarks.
- Widest single gap
- Vending-Bench 2: Claude Haiku 5.5 $3,602 against Claude Opus 5 $11,182, 47.4 points apart on a 0 to 100 scale.
- Output price
- Claude Haiku 5.5 $0.50 against Claude Opus 5 $25.00 per million output tokens, 50.0x apart.
- Context window
- Both take 1M tokens.
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 5 | Ties |
|---|---|---|---|---|
| Coding | 3 | 11 | ||
| Intelligence | 0 | 2 | ||
| Agentic work | 0 | 13 | ||
| Reasoning | 1 | 8 | ||
| Math | 0 | 3 | 1 tie | |
| Knowledge | 0 | 2 | ||
| Web design | 2 | 5 | ||
| General | 1 | 7 | ||
| All shared boards | 7 | 51 | 1 tie |
CodingLike-for-likeFour of these boards feed the Vibe Coding Index311
| Benchmark | Claude Haiku 5.5 | Claude Opus 5 | Leader |
|---|---|---|---|
| LiveBench coding | 91.4% | 90.8% | Claude Haiku 5.5 |
| LMArena WebDev | 1586 | 1689 | Claude Opus 5 |
| AA Coding Index | Not measured | 78.0 | Only Claude Opus 5 measured |
| LiveCodeBench (Vals AI) | Not measured | 89.0% | Only Claude Opus 5 measured |
| SWE-bench Verified (Vals AI) | Not measured | 97.0% | Only Claude Opus 5 measured |
| Terminal-Bench 4 (Vals AI) | 36.4% | 53.5% | Claude Opus 5 |
| Vibe Code Bench (Vals AI) | 90.4% | 88.4% | Claude Haiku 5.5 |
| Code migration (Vals AI) | 44.6% | 57.5% | Claude Opus 5 |
| ProgramBench (Vals AI) | 2.5% | 3.0% | Claude Opus 5 |
| IOI (Vals AI) | 47.3% | 84.3% | Claude Opus 5 |
| Terminal-Bench 2.1 (Vals AI) | Not measured | 84.6% | Only Claude Opus 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% | 28.5% | Claude Opus 5 |
| SkillsBench (Vals AI) | Not measured | 60.4% | Only Claude Opus 5 measured |
| CyberBench (Vals AI) | 75.5% | 65.4% | Claude Haiku 5.5 |
| SciCode | 55.0% | 56.4% | Claude Opus 5 |
| FrontierCode | 46.4% | 53.4% | Claude Opus 5 |
| FrontierSWE | 43.8% | 52.0% | Claude Opus 5 |
| WeirdML | Not measured | 91.8% | Only Claude Opus 5 measured |
| ALE-Bench | Not measured | 2164.6 | Only Claude Opus 5 measured |
| LMArena Text: coding | Not measured | 1533 | Only Claude Opus 5 measured |
| LMArena Text: software and IT | Not measured | 1527 | Only Claude Opus 5 measured |
| LMArena WebDev: React | 1605 | 1711 | Claude Opus 5 |
| LMArena WebDev: HTML | 1569 | 1680 | Claude Opus 5 |
| LMArena WebDev: from an image | Not measured | 1662 | Only Claude Opus 5 measured |
| Neither model has a result on the other 13 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index02
| Benchmark | Claude Haiku 5.5 | Claude Opus 5 | Leader |
|---|---|---|---|
| AA Intelligence Index | 43.4 | 50.8 | Claude Opus 5 |
| Epoch Capabilities Index | 159.3 | 163.9 | Claude Opus 5 |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index013
| Benchmark | Claude Haiku 5.5 | Claude Opus 5 | Leader |
|---|---|---|---|
| AA Agentic Index | Not measured | 56.5 | Only Claude Opus 5 measured |
| Design Arena: agents building web apps | Not measured | 1266 | Only Claude Opus 5 measured |
| Design Arena: agents building full-stack apps | Not measured | 1306 | Only Claude Opus 5 measured |
| Design Arena: agents building mobile apps | Not measured | 1348 | Only Claude Opus 5 measured |
| Design Arena: agents building Android apps | Not measured | 1258 | Only Claude Opus 5 measured |
| Design Arena: agents building Godot games | Not measured | 1279 | Only Claude Opus 5 measured |
| Design Arena: agents building games | Not measured | 1261 | Only Claude Opus 5 measured |
| Design Arena: PowerPoint slides | Not measured | 1265 | Only Claude Opus 5 measured |
| LiveBench research | 81.9% | 88.9% | Claude Opus 5 |
| LiveBench browser | 80.0% | 84.0% | Claude Opus 5 |
| LiveBench long agentic | 57.6% | 62.1% | Claude Opus 5 |
| SREBench (Vals AI) | 5.7% | 12.2% | Claude Opus 5 |
| Finance Agent (Vals AI) | 54.1% | 58.6% | Claude Opus 5 |
| Tax Agent Bench (Vals AI) | 31.9% | 45.5% | Claude Opus 5 |
| Legal Research Bench (Vals AI) | 43.3% | 55.3% | Claude Opus 5 |
| Harvey's Legal Agent Benchmark (Vals AI) | 4.2% | Not measured | Only Claude Haiku 5.5 measured |
| Excel Modeling Benchmark (Vals AI) | 59.0% | 73.6% | Claude Opus 5 |
| BioMysteryBench (Vals AI) | 70.4% | 79.3% | Claude Opus 5 |
| Terminal-Bench-Science (Vals AI) | 10.0% | 27.1% | Claude Opus 5 |
| Vals Science Index | 38.5% | 47.9% | Claude Opus 5 |
| Time Horizon Index (Vals AI) | Not measured | 18.8% | Only Claude Opus 5 measured |
| CUA-bench (Vals AI) | Not measured | 9.0% | Only Claude Opus 5 measured |
| APEX-Agents | 56.1% | 65.8% | Claude Opus 5 |
| OSWorld 2.0 | Not measured | 31.4% | Only Claude Opus 5 measured |
| BALROG | Not measured | 63.4% | Only Claude Opus 5 measured |
| PostTrainBench | Not measured | 35.0% | Only Claude Opus 5 measured |
| Vending-Bench 2 | $3,602 | $11,182 | Claude Opus 5 |
| LMArena Search | Not measured | 1242 | Only Claude Opus 5 measured |
| Neither model has a result on the other 11 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index18
| Benchmark | Claude Haiku 5.5 | Claude Opus 5 | Leader |
|---|---|---|---|
| GPQA Diamond | Not measured | 93.4% | Only Claude Opus 5 measured |
| LiveBench reasoning | 82.4% | 91.2% | Claude Opus 5 |
| MysteryMechanism (Vals AI) | 35.1% | 37.4% | Claude Opus 5 |
| MMMU Pro (Vals AI) | Not measured | 89.9% | Only Claude Opus 5 measured |
| GPQA Diamond (Artificial Analysis run) | Not measured | 93.7% | Only Claude Opus 5 measured |
| Humanity's Last Exam (Artificial Analysis run) | 44.4% | 54.9% | Claude Opus 5 |
| GPQA Diamond (Epoch AI run) | 89.6% | 93.9% | Claude Opus 5 |
| ARC-AGI | 89.0% | 97.5% | Claude Opus 5 |
| ARC-AGI-2 | 61.3% | 90.4% | Claude Opus 5 |
| SimpleBench | Not measured | 80.6% | Only Claude Opus 5 measured |
| Chess puzzles | 55.0% | 43.0% | Claude Haiku 5.5 |
| Mystery game puzzles | 30.0% | 59.0% | Claude Opus 5 |
| EBR-bench | 43.8% | 45.7% | Claude Opus 5 |
| LMArena Text: hard prompts | Not measured | 1527 | Only Claude Opus 5 measured |
| LMArena Text: expert | Not measured | 1554 | Only Claude Opus 5 measured |
| LMArena Text: hard prompts in English | Not measured | 1523 | Only Claude Opus 5 measured |
| LMArena Vision: diagrams | Not measured | 1348 | Only Claude Opus 5 measured |
| LMArena Vision: homework | Not measured | 1338 | Only Claude Opus 5 measured |
| Neither model has a result on the other 3 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index03
| Benchmark | Claude Haiku 5.5 | Claude Opus 5 | Leader |
|---|---|---|---|
| OTIS Mock AIME | 98.9% | 98.9% | Tie |
| FrontierMath, tiers 1 to 3 | 75.1% | 85.6% | Claude Opus 5 |
| FrontierMath, tier 4 | 46.3% | 73.2% | Claude Opus 5 |
| ProofBench | 89.0% | 99.0% | Claude Opus 5 |
| LMArena Text: math | Not measured | 1533 | Only Claude Opus 5 measured |
| LMArena Text: mathematical work | Not measured | 1544 | Only Claude Opus 5 measured |
| Neither model has a result on the other 7 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index02
| Benchmark | Claude Haiku 5.5 | Claude Opus 5 | Leader |
|---|---|---|---|
| MMLU Pro | Not measured | 91.6% | Only Claude Opus 5 measured |
| LegalBench (Vals AI) | Not measured | 87.0% | Only Claude Opus 5 measured |
| CorpFin (Vals AI) | Not measured | 73.2% | Only Claude Opus 5 measured |
| TaxEval (Vals AI) | Not measured | 75.1% | Only Claude Opus 5 measured |
| MortgageTax (Vals AI) | Not measured | 72.1% | Only Claude Opus 5 measured |
| MedCode (Vals AI) | 51.5% | 63.6% | Claude Opus 5 |
| SimpleQA Verified | 23.8% | 59.9% | Claude Opus 5 |
| LMArena Text: science | Not measured | 1531 | Only Claude Opus 5 measured |
| LMArena Text: medicine and healthcare | Not measured | 1525 | Only Claude Opus 5 measured |
| LMArena Text: legal and government | Not measured | 1530 | Only Claude Opus 5 measured |
| LMArena Text: business and finance | Not measured | 1501 | Only Claude Opus 5 measured |
| Neither model has a result on the other 6 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index25
| Benchmark | Claude Haiku 5.5 | Claude Opus 5 | Leader |
|---|---|---|---|
| Design Arena: websites | 1263 | 1309 | Claude Opus 5 |
| Design Arena: UI components | 1295 | 1348 | Claude Opus 5 |
| Design Arena: game dev | 1315 | 1339 | Claude Opus 5 |
| Design Arena: data viz | 1292 | 1329 | Claude Opus 5 |
| Design Arena: 3D | 1343 | 1335 | Claude Haiku 5.5 |
| Design Arena: all code categories | 1279 | 1324 | Claude Opus 5 |
| Design Arena: SVG | Not measured | 1310 | Only Claude Opus 5 measured |
| Design Arena: ASCII art | Not measured | 1352 | Only Claude Opus 5 measured |
| LiveBench design | 83.1% | 83.0% | Claude Haiku 5.5 |
GeneralLike-for-likePublic boards, shown as published, kept out of the index17
| Benchmark | Claude Haiku 5.5 | Claude Opus 5 | Leader |
|---|---|---|---|
| Vals Index | 58.7% | Not measured | Only Claude Haiku 5.5 measured |
| LiveBench data analysis | 53.1% | 74.6% | Claude Opus 5 |
| Public Benefits Bench (Vals AI) | 63.2% | 76.9% | Claude Opus 5 |
| SAGE (Vals AI) | 45.8% | 49.4% | Claude Opus 5 |
| MedScribe (Vals AI) | 89.5% | 91.0% | Claude Opus 5 |
| Vals Multimodal Index | Not measured | 73.9% | Only Claude Opus 5 measured |
| Long context reasoning (AA-LCR) | 82.7% | 82.0% | Claude Haiku 5.5 |
| DTBench | 95.0% | 97.9% | Claude Opus 5 |
| LMCA | 51.1% | 64.5% | Claude Opus 5 |
| Furniture assembly | 47.5% | 60.8% | Claude Opus 5 |
| LMArena Text | Not measured | 1509 | Only Claude Opus 5 measured |
| LMArena Text: instruction following | Not measured | 1518 | Only Claude Opus 5 measured |
| LMArena Text: creative writing | Not measured | 1493 | Only Claude Opus 5 measured |
| LMArena Vision | Not measured | 1320 | Only Claude Opus 5 measured |
| LMArena Text: English | Not measured | 1508 | Only Claude Opus 5 measured |
| LMArena Text: non-English | Not measured | 1502 | Only Claude Opus 5 measured |
| LMArena Text: Chinese | Not measured | 1573 | Only Claude Opus 5 measured |
| LMArena Text: German | Not measured | 1527 | Only Claude Opus 5 measured |
| LMArena Text: Japanese | Not measured | 1520 | Only Claude Opus 5 measured |
| LMArena Text: Korean | Not measured | 1517 | Only Claude Opus 5 measured |
| LMArena Text: French | Not measured | 1519 | Only Claude Opus 5 measured |
| LMArena Text: Spanish | Not measured | 1523 | Only Claude Opus 5 measured |
| LMArena Text: Russian | Not measured | 1507 | Only Claude Opus 5 measured |
| LMArena Text: Polish | Not measured | 1522 | Only Claude Opus 5 measured |
| LMArena Text: multi-turn | Not measured | 1500 | Only Claude Opus 5 measured |
| LMArena Text: longer queries | Not measured | 1517 | Only Claude Opus 5 measured |
| LMArena Text: writing and language | Not measured | 1499 | Only Claude Opus 5 measured |
| LMArena Text: entertainment and media | Not measured | 1481 | Only Claude Opus 5 measured |
| LMArena Vision: English | Not measured | 1315 | Only Claude Opus 5 measured |
| LMArena Vision: Chinese | Not measured | 1400 | Only Claude Opus 5 measured |
| LMArena Vision: reading text | Not measured | 1329 | Only Claude Opus 5 measured |
| LMArena Vision: humor | Not measured | 1293 | Only Claude Opus 5 measured |
| LMArena Vision: creative writing | Not measured | 1313 | Only Claude Opus 5 measured |
| LMArena Document | Not measured | 1516 | Only Claude Opus 5 measured |
| Neither model has a result on the other 12 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Claude Haiku 5.5 | Claude Opus 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 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 5 |
|---|---|---|
| Maker | Anthropic | Anthropic |
| Weights | No public weights listed | No public weights listed |
| Released | October 7, 2026 | July 24, 2026 |
| Context window | 1M | 1M |
| Input $/Mtok | $0.10 | $5.00 |
| Output $/Mtok | $0.50 | $25.00 |
| Coding index | 75.9 | 81.8 |
| Independent measurements behind it | 2 | 2 |
| Cost per solved task | Not computable | $1.33 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Claude Haiku 5.5 better than Claude Opus 5 for coding?
Pick Claude Opus 5 for coding: it scores 81.8 on the Vibe Coding Index against 75.9 for Claude Haiku 5.5. Pick Claude Haiku 5.5 when output tokens cost 50.0x less, or when what matters is LiveBench coding or Vibe Code Bench (Vals AI), where it leads.
Which is cheaper, Claude Haiku 5.5 or Claude Opus 5?
Claude Haiku 5.5 costs $0.10 per million input tokens and $0.50 per million output tokens; Claude Opus 5 costs $5.00 and $25.00. Cost per solved task is known for Claude Opus 5 only.
Which has the bigger context window, Claude Haiku 5.5 or Claude Opus 5?
Neither: both take 1M tokens.
How many benchmarks is the Claude Haiku 5.5 vs Claude Opus 5 comparison based on?
59 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 5's on 2. Where only one model has a result, the page says so instead of naming a winner.