Claude Haiku 5.5 vs Grok 4.3
Updated October 21, 2026. 34 benchmarks have a result for both. Coding is ranked on the Vibe Coding Index; every other board is shown as published.
vs boards won of 34 shared
Decision reading
Pick Claude Haiku 5.5 for coding: it scores 75.9 on the Vibe Coding Index against 22.5 for Grok 4.3.
Pick Grok 4.3 when the benchmark that matters is SimpleQA Verified, where it leads.
Model AClaude Haiku 5.5Anthropic75.9/1002 independent benchmarksNo cost per solved taskModel BGrok 4.3xAI22.5/1001 independent benchmark$0.31 per solved task
- Shared results
- 34
- Claude Haiku 5.5 only
- 28
- Grok 4.3 only
- 70
- 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 Haiku 5.5
Claude Haiku 5.5 scores 75.9 against 22.5.
2 and 1 benchmarks behind the scores
Intelligence
AA Intelligence Index
Claude Haiku 5.5
Claude Haiku 5.5 leads, 43.4 against 24.9.
Same board, both measured
Agentic work
AA Agentic Index
No call
Only Grok 4.3 has a AA Agentic Index result, 15.5.
Directional only
Reasoning
GPQA Diamond
No call
Only Grok 4.3 has a GPQA Diamond result, 91.4%.
Directional only
Knowledge
MMLU Pro
No call
Only Grok 4.3 has a MMLU Pro result, 85.8%.
Directional only
Web design
Design Arena: websites
Claude Haiku 5.5
Claude Haiku 5.5 leads, 1263 against 1196.
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, Grok 4.3 $0.0025 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only Grok 4.3 has the number, $0.31.
Directional only
At a glance
- Coding index
- Claude Haiku 5.5 75.9 from 2 benchmarks, Grok 4.3 22.5 from 1 benchmark.
- Widest category
- Math, 36.9 points apart on average over 4 shared benchmarks.
- Widest single gap
- ProofBench: Claude Haiku 5.5 89.0% against Grok 4.3 11.0%, 78.0 points apart on a 0 to 100 scale.
- Output price
- Claude Haiku 5.5 $0.50 against Grok 4.3 $2.50 per million output tokens, 5.0x 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 | Grok 4.3 | Ties |
|---|---|---|---|---|
| Coding | 7 | 0 | ||
| Intelligence | 1 | 0 | ||
| Agentic work | 5 | 0 | ||
| Reasoning | 3 | 0 | ||
| Math | 4 | 0 | ||
| Knowledge | 1 | 1 | ||
| Web design | 6 | 0 | ||
| General | 6 | 0 | ||
| All shared boards | 33 | 1 |
CodingLike-for-likeFour of these boards feed the Vibe Coding Index70
| Benchmark | Claude Haiku 5.5 | Grok 4.3 | Leader |
|---|---|---|---|
| LiveBench coding | 91.4% | Not measured | Only Claude Haiku 5.5 measured |
| LMArena WebDev | 1586 | 1358 | Claude Haiku 5.5 |
| AA Coding Index | Not measured | 42.2 | Only Grok 4.3 measured |
| LiveCodeBench (Vals AI) | Not measured | 84.5% | Only Grok 4.3 measured |
| SWE-bench Verified (Vals AI) | Not measured | 71.4% | Only Grok 4.3 measured |
| Terminal-Bench 4 (Vals AI) | 36.4% | Not measured | Only Claude Haiku 5.5 measured |
| Vibe Code Bench (Vals AI) | 90.4% | 19.4% | Claude Haiku 5.5 |
| Code migration (Vals AI) | 44.6% | 6.8% | Claude Haiku 5.5 |
| ProgramBench (Vals AI) | 2.5% | 0.0% | Claude Haiku 5.5 |
| IOI (Vals AI) | 47.3% | Not measured | Only Claude Haiku 5.5 measured |
| Terminal-Bench 2.1 (Vals AI) | Not measured | 42.0% | Only Grok 4.3 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 |
| SkillsBench (Vals AI) | Not measured | 40.6% | Only Grok 4.3 measured |
| CyberBench (Vals AI) | 75.5% | Not measured | Only Claude Haiku 5.5 measured |
| SciCode | 55.0% | 48.3% | Claude Haiku 5.5 |
| Terminal-Bench Hard (Artificial Analysis run) | Not measured | 37.9% | Only Grok 4.3 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 | 49.9% | Only Grok 4.3 measured |
| ALE-Bench | Not measured | 944.2 | Only Grok 4.3 measured |
| LMArena Text: coding | Not measured | 1415 | Only Grok 4.3 measured |
| LMArena Text: software and IT | Not measured | 1416 | Only Grok 4.3 measured |
| LMArena WebDev: React | 1605 | 1353 | Claude Haiku 5.5 |
| LMArena WebDev: HTML | 1569 | 1367 | Claude Haiku 5.5 |
| LMArena WebDev: from an image | Not measured | 1375 | Only Grok 4.3 measured |
| Neither model has a result on the other 12 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Claude Haiku 5.5 | Grok 4.3 | Leader |
|---|---|---|---|
| AA Intelligence Index | 43.4 | 24.9 | Claude Haiku 5.5 |
| Epoch Capabilities Index | 159.3 | Not measured | Only Claude Haiku 5.5 measured |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index50
| Benchmark | Claude Haiku 5.5 | Grok 4.3 | Leader |
|---|---|---|---|
| AA Agentic Index | Not measured | 15.5 | Only Grok 4.3 measured |
| Design Arena: agents building web apps | Not measured | 1126 | Only Grok 4.3 measured |
| Design Arena: agents building full-stack apps | Not measured | 1006 | Only Grok 4.3 measured |
| Design Arena: agents building mobile apps | Not measured | 1059 | Only Grok 4.3 measured |
| Design Arena: agents building Android apps | Not measured | 967 | Only Grok 4.3 measured |
| Design Arena: agents building Godot games | Not measured | 914 | Only Grok 4.3 measured |
| Design Arena: agents building games | Not measured | 1007 | Only Grok 4.3 measured |
| Design Arena: HTML slides | Not measured | 1008 | Only Grok 4.3 measured |
| Design Arena: PowerPoint slides | Not measured | 1012 | Only Grok 4.3 measured |
| 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% | 37.7% | Claude Haiku 5.5 |
| Tax Agent Bench (Vals AI) | 31.9% | 6.2% | Claude Haiku 5.5 |
| Legal Research Bench (Vals AI) | 43.3% | 15.4% | Claude Haiku 5.5 |
| Harvey's Legal Agent Benchmark (Vals AI) | 4.2% | Not measured | Only Claude Haiku 5.5 measured |
| Excel Modeling Benchmark (Vals AI) | 59.0% | 18.4% | Claude Haiku 5.5 |
| 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 |
| τ²-Bench Telecom | Not measured | 97.7% | Only Grok 4.3 measured |
| APEX-Agents | 56.1% | Not measured | Only Claude Haiku 5.5 measured |
| Vending-Bench 2 | $3,602 | $35 | Claude Haiku 5.5 |
| LMArena Search | Not measured | 1166 | Only Grok 4.3 measured |
| Neither model has a result on the other 14 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index30
| Benchmark | Claude Haiku 5.5 | Grok 4.3 | Leader |
|---|---|---|---|
| GPQA Diamond | Not measured | 91.4% | Only Grok 4.3 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 | 83.1% | Only Grok 4.3 measured |
| GPQA Diamond (Artificial Analysis run) | Not measured | 90.1% | Only Grok 4.3 measured |
| Humanity's Last Exam (Artificial Analysis run) | 44.4% | 37.2% | Claude Haiku 5.5 |
| GPQA Diamond (Epoch AI run) | 89.6% | 88.8% | 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 |
| Chess puzzles | 55.0% | 18.0% | Claude Haiku 5.5 |
| Mystery game puzzles | 30.0% | Not measured | Only Claude Haiku 5.5 measured |
| EBR-bench | 43.8% | Not measured | Only Claude Haiku 5.5 measured |
| LMArena Text: hard prompts | Not measured | 1396 | Only Grok 4.3 measured |
| LMArena Text: expert | Not measured | 1384 | Only Grok 4.3 measured |
| LMArena Text: hard prompts in English | Not measured | 1402 | Only Grok 4.3 measured |
| LMArena Vision: diagrams | Not measured | 1241 | Only Grok 4.3 measured |
| LMArena Vision: homework | Not measured | 1241 | Only Grok 4.3 measured |
| Neither model has a result on the other 4 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index40
| Benchmark | Claude Haiku 5.5 | Grok 4.3 | Leader |
|---|---|---|---|
| OTIS Mock AIME | 98.9% | 93.3% | Claude Haiku 5.5 |
| FrontierMath, tiers 1 to 3 | 75.1% | 42.8% | Claude Haiku 5.5 |
| FrontierMath, tier 4 | 46.3% | 14.6% | Claude Haiku 5.5 |
| ProofBench | 89.0% | 11.0% | Claude Haiku 5.5 |
| LMArena Text: math | Not measured | 1387 | Only Grok 4.3 measured |
| LMArena Text: mathematical work | Not measured | 1396 | Only Grok 4.3 measured |
| Neither model has a result on the other 7 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index11
| Benchmark | Claude Haiku 5.5 | Grok 4.3 | Leader |
|---|---|---|---|
| MMLU Pro | Not measured | 85.8% | Only Grok 4.3 measured |
| LegalBench (Vals AI) | Not measured | 84.5% | Only Grok 4.3 measured |
| CaseLaw (Vals AI) | Not measured | 79.3% | Only Grok 4.3 measured |
| CorpFin (Vals AI) | Not measured | 68.5% | Only Grok 4.3 measured |
| TaxEval (Vals AI) | Not measured | 70.8% | Only Grok 4.3 measured |
| MortgageTax (Vals AI) | Not measured | 48.3% | Only Grok 4.3 measured |
| MedCode (Vals AI) | 51.5% | 38.1% | Claude Haiku 5.5 |
| SimpleQA Verified | 23.8% | 33.2% | Grok 4.3 |
| LMArena Text: science | Not measured | 1399 | Only Grok 4.3 measured |
| LMArena Text: medicine and healthcare | Not measured | 1384 | Only Grok 4.3 measured |
| LMArena Text: legal and government | Not measured | 1386 | Only Grok 4.3 measured |
| LMArena Text: business and finance | Not measured | 1381 | Only Grok 4.3 measured |
| Neither model has a result on the other 5 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index60
| Benchmark | Claude Haiku 5.5 | Grok 4.3 | Leader |
|---|---|---|---|
| Design Arena: websites | 1263 | 1196 | Claude Haiku 5.5 |
| Design Arena: UI components | 1295 | 1192 | Claude Haiku 5.5 |
| Design Arena: game dev | 1315 | 1174 | Claude Haiku 5.5 |
| Design Arena: data viz | 1292 | 1180 | Claude Haiku 5.5 |
| Design Arena: 3D | 1343 | 1125 | Claude Haiku 5.5 |
| Design Arena: all code categories | 1279 | 1187 | Claude Haiku 5.5 |
| Design Arena: SVG | Not measured | 1081 | Only Grok 4.3 measured |
| Design Arena: ASCII art | Not measured | 1125 | Only Grok 4.3 measured |
| LiveBench design | 83.1% | Not measured | Only Claude Haiku 5.5 measured |
GeneralLike-for-likePublic boards, shown as published, kept out of the index60
| Benchmark | Claude Haiku 5.5 | Grok 4.3 | 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% | 51.7% | Claude Haiku 5.5 |
| SAGE (Vals AI) | 45.8% | 19.7% | Claude Haiku 5.5 |
| MedScribe (Vals AI) | 89.5% | 74.4% | Claude Haiku 5.5 |
| Vals Multimodal Index | Not measured | 43.3% | Only Grok 4.3 measured |
| IFBench | Not measured | 83.3% | Only Grok 4.3 measured |
| Long context reasoning (AA-LCR) | 82.7% | 75.0% | Claude Haiku 5.5 |
| DTBench | 95.0% | 90.7% | Claude Haiku 5.5 |
| LMCA | 51.1% | 38.3% | Claude Haiku 5.5 |
| Furniture assembly | 47.5% | Not measured | Only Claude Haiku 5.5 measured |
| LMArena Text | Not measured | 1397 | Only Grok 4.3 measured |
| LMArena Text: instruction following | Not measured | 1366 | Only Grok 4.3 measured |
| LMArena Text: creative writing | Not measured | 1380 | Only Grok 4.3 measured |
| LMArena Vision | Not measured | 1229 | Only Grok 4.3 measured |
| LMArena Text: English | Not measured | 1404 | Only Grok 4.3 measured |
| LMArena Text: non-English | Not measured | 1385 | Only Grok 4.3 measured |
| LMArena Text: Chinese | Not measured | 1422 | Only Grok 4.3 measured |
| LMArena Text: German | Not measured | 1395 | Only Grok 4.3 measured |
| LMArena Text: Japanese | Not measured | 1379 | Only Grok 4.3 measured |
| LMArena Text: Korean | Not measured | 1354 | Only Grok 4.3 measured |
| LMArena Text: French | Not measured | 1411 | Only Grok 4.3 measured |
| LMArena Text: Spanish | Not measured | 1399 | Only Grok 4.3 measured |
| LMArena Text: Russian | Not measured | 1399 | Only Grok 4.3 measured |
| LMArena Text: Polish | Not measured | 1398 | Only Grok 4.3 measured |
| LMArena Text: multi-turn | Not measured | 1406 | Only Grok 4.3 measured |
| LMArena Text: longer queries | Not measured | 1393 | Only Grok 4.3 measured |
| LMArena Text: writing and language | Not measured | 1385 | Only Grok 4.3 measured |
| LMArena Text: entertainment and media | Not measured | 1370 | Only Grok 4.3 measured |
| LMArena Vision: English | Not measured | 1235 | Only Grok 4.3 measured |
| LMArena Vision: Chinese | Not measured | 1257 | Only Grok 4.3 measured |
| LMArena Vision: reading text | Not measured | 1235 | Only Grok 4.3 measured |
| LMArena Vision: humor | Not measured | 1222 | Only Grok 4.3 measured |
| LMArena Vision: recognizing things | Not measured | 1217 | Only Grok 4.3 measured |
| LMArena Vision: creative writing | Not measured | 1237 | Only Grok 4.3 measured |
| Neither model has a result on the other 11 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Claude Haiku 5.5 | Grok 4.3 | 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$0.0003Fits in one request
Grok 4.3$0.0025Fits in one request
Claude Haiku 5.5 costs less
Repository review
50K input + 3K output tokens
Claude Haiku 5.5$0.0065Fits in one request
Grok 4.3$0.070Fits in one request
Claude Haiku 5.5 costs less
Agent loop
200K input + 10K output tokens
Claude Haiku 5.5$0.025Fits in one request
Grok 4.3$0.275Fits in one request
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 | SpaceXAI Grok 4.3 |
|---|---|---|
| Maker | Anthropic | xAI |
| Weights | No public weights listed | No public weights listed |
| Released | October 7, 2026 | April 30, 2026 |
| Context window | 1M | 1M |
| Input $/Mtok | $0.10 | $1.25 |
| Output $/Mtok | $0.50 | $2.50 |
| Coding index | 75.9 | 22.5 |
| Independent measurements behind it | 2 | 1 |
| Cost per solved task | Not computable | $0.31 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Claude Haiku 5.5 better than Grok 4.3 for coding?
Pick Claude Haiku 5.5 for coding: it scores 75.9 on the Vibe Coding Index against 22.5 for Grok 4.3. Pick Grok 4.3 when the benchmark that matters is SimpleQA Verified, where it leads.
Which is cheaper, Claude Haiku 5.5 or Grok 4.3?
Claude Haiku 5.5 costs $0.10 per million input tokens and $0.50 per million output tokens; Grok 4.3 costs $1.25 and $2.50. Cost per solved task is known for Grok 4.3 only.
Which has the bigger context window, Claude Haiku 5.5 or Grok 4.3?
Neither: both take 1M tokens.
How many benchmarks is the Claude Haiku 5.5 vs Grok 4.3 comparison based on?
34 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 Grok 4.3's on 1. Where only one model has a result, the page says so instead of naming a winner.