Grok 4.5 vs Hy4 preview
Grok 4.5 leads Hy4 preview on coding, 58.6 to 44.3 on the Vibe Coding Index, and Hy4 preview costs 2.7x less per output token ($2.2509 vs $6.00 per million). Updated October 21, 2026; 19 benchmarks have a result for both.
Grok 4.5 or Hy4 preview: which to pick
Pick Grok 4.5 for coding: it scores 58.6 on the Vibe Coding Index against 44.3 for Hy4 preview.
Pick Hy4 preview for output tokens 2.7x cheaper ($2.2509 vs $6.00 per million) and a larger context window (1.05M against 500K tokens).
- Shared results
- 19
- Grok 4.5 only
- 104
- Hy4 preview only
- 5
- Like-for-like categories
- 5 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
Grok 4.5
Grok 4.5 scores 58.6 against 44.3.
6 and 3 benchmarks behind the scores
Intelligence
AA Intelligence Index
No call
Only Grok 4.5 has a AA Intelligence Index result, 38.8.
Directional only
Agentic work
AA Agentic Index
No call
Only Grok 4.5 has a AA Agentic Index result, 41.2.
Directional only
Reasoning
GPQA Diamond
No call
Only Grok 4.5 has a GPQA Diamond result, 92.9%.
Directional only
Knowledge
MMLU Pro
No call
Only Grok 4.5 has a MMLU Pro result, 89.2%.
Directional only
Web design
Design Arena: websites
No call
Only Grok 4.5 has a Design Arena: websites result, 1281.
Directional only
General
Vals Index
No call
Only Hy4 preview has a Vals Index result, 53.2%.
Directional only
Long documents
Listed context window
Hy4 preview
Hy4 preview takes 1.05M tokens against 500K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Hy4 preview
Grok 4.5 $0.0050, Hy4 preview $0.0019 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only Grok 4.5 has the number, $0.62.
Directional only
At a glance
- Coding index
- Grok 4.5 58.6 from 6 benchmarks, Hy4 preview 44.3 from 3 benchmarks.
- Widest category
- Math, 44.0 points apart on average over 1 shared benchmark.
- Widest single gap
- ProofBench: Grok 4.5 31.0% against Hy4 preview 75.0%, 44.0 points apart on a 0 to 100 scale.
- Output price
- Grok 4.5 $6.00 against Hy4 preview $2.2509 per million output tokens, 2.7x apart.
- Context window
- Grok 4.5 takes 500K tokens, Hy4 preview 1.05M.
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 | Grok 4.5 | Bars | Hy4 preview | Ties |
|---|---|---|---|---|
| Coding | 3 | 6 | 1 tie | |
| Agentic work | 0 | 5 | ||
| Math | 0 | 1 | ||
| Knowledge | 2 | 0 | ||
| General | 1 | 0 | ||
| All shared boards | 6 | 12 | 1 tie |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index36
| Benchmark | Grok 4.5 | Hy4 preview | Leader |
|---|---|---|---|
| LiveBench coding | 94.3% | Not measured | Only Grok 4.5 measured |
| LMArena WebDev | 1553 | 1631 | Hy4 preview |
| AA Coding Index | 72.4 | Not measured | Only Grok 4.5 measured |
| LiveCodeBench (Vals AI) | 87.3% | Not measured | Only Grok 4.5 measured |
| SWE-bench Verified (Vals AI) | 86.6% | Not measured | Only Grok 4.5 measured |
| Terminal-Bench 4 (Vals AI) | 8.6% | 8.1% | Grok 4.5 |
| Vibe Code Bench (Vals AI) | 69.0% | 77.5% | Hy4 preview |
| Code migration (Vals AI) | 36.6% | 47.4% | Hy4 preview |
| ProgramBench (Vals AI) | 0.0% | 0.0% | Tie |
| IOI (Vals AI) | 40.6% | 59.3% | Hy4 preview |
| Terminal-Bench 2.1 (Vals AI) | 67.8% | 55.1% | Grok 4.5 |
| SkillsBench (Vals AI) | 66.0% | Not measured | Only Grok 4.5 measured |
| CyberBench (Vals AI) | 71.0% | 65.4% | Grok 4.5 |
| SciCode | 55.0% | Not measured | Only Grok 4.5 measured |
| FrontierCode | 42.4% | Not measured | Only Grok 4.5 measured |
| WeirdML | 46.4% | Not measured | Only Grok 4.5 measured |
| ALE-Bench | 1309.3 | Not measured | Only Grok 4.5 measured |
| LMArena Text: coding | 1474 | Not measured | Only Grok 4.5 measured |
| LMArena Text: software and IT | 1471 | Not measured | Only Grok 4.5 measured |
| LMArena WebDev: React | 1556 | 1653 | Hy4 preview |
| LMArena WebDev: HTML | 1567 | 1620 | Hy4 preview |
| LMArena WebDev: from an image | 1562 | Not measured | Only Grok 4.5 measured |
| SciCode | 6.5% | Not measured | Only Grok 4.5 measured |
| Neither model has a result on the other 16 boards here | |||
IntelligenceDirectional onlyPublic boards, shown as published, kept out of the index2 boards, none shared
| Benchmark | Grok 4.5 | Hy4 preview | Leader |
|---|---|---|---|
| AA Intelligence Index | 38.8 | Not measured | Only Grok 4.5 measured |
| Epoch Capabilities Index | 154.1 | Not measured | Only Grok 4.5 measured |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index05
| Benchmark | Grok 4.5 | Hy4 preview | Leader |
|---|---|---|---|
| AA Agentic Index | 41.2 | Not measured | Only Grok 4.5 measured |
| Design Arena: agents building web apps | 1218 | Not measured | Only Grok 4.5 measured |
| Design Arena: agents building full-stack apps | 1249 | Not measured | Only Grok 4.5 measured |
| Design Arena: agents building mobile apps | 1221 | Not measured | Only Grok 4.5 measured |
| Design Arena: agents building Android apps | 1242 | Not measured | Only Grok 4.5 measured |
| Design Arena: agents building Godot games | 1229 | Not measured | Only Grok 4.5 measured |
| Design Arena: agents building games | 1236 | Not measured | Only Grok 4.5 measured |
| Design Arena: HTML slides | 1204 | Not measured | Only Grok 4.5 measured |
| Design Arena: PowerPoint slides | 1233 | Not measured | Only Grok 4.5 measured |
| LiveBench research | 85.9% | Not measured | Only Grok 4.5 measured |
| LiveBench browser | 44.0% | Not measured | Only Grok 4.5 measured |
| LiveBench long agentic | 27.9% | Not measured | Only Grok 4.5 measured |
| SREBench (Vals AI) | 0.8% | 2.3% | Hy4 preview |
| Finance Agent (Vals AI) | 48.4% | 55.1% | Hy4 preview |
| Tax Agent Bench (Vals AI) | 24.9% | 32.6% | Hy4 preview |
| Legal Research Bench (Vals AI) | 38.0% | 45.2% | Hy4 preview |
| Harvey's Legal Agent Benchmark (Vals AI) | Not measured | 8.8% | Only Hy4 preview measured |
| Excel Modeling Benchmark (Vals AI) | 52.9% | 58.1% | Hy4 preview |
| BioMysteryBench (Vals AI) | Not measured | 69.3% | Only Hy4 preview measured |
| Terminal-Bench-Science (Vals AI) | Not measured | 1.4% | Only Hy4 preview measured |
| Time Horizon Index (Vals AI) | 6.3% | Not measured | Only Grok 4.5 measured |
| APEX-Agents | 56.2% | Not measured | Only Grok 4.5 measured |
| PostTrainBench | 23.4% | Not measured | Only Grok 4.5 measured |
| Vending-Bench 2 | $3,887 | Not measured | Only Grok 4.5 measured |
| LMArena Search | 1216 | Not measured | Only Grok 4.5 measured |
| Neither model has a result on the other 16 boards here | |||
ReasoningDirectional onlyPublic boards, shown as published, kept out of the index16 boards, none shared
| Benchmark | Grok 4.5 | Hy4 preview | Leader |
|---|---|---|---|
| GPQA Diamond | 92.9% | Not measured | Only Grok 4.5 measured |
| LiveBench reasoning | 87.2% | Not measured | Only Grok 4.5 measured |
| MMMU Pro (Vals AI) | 61.8% | Not measured | Only Grok 4.5 measured |
| GPQA Diamond (Artificial Analysis run) | 93.1% | Not measured | Only Grok 4.5 measured |
| Humanity's Last Exam (Artificial Analysis run) | 42.7% | Not measured | Only Grok 4.5 measured |
| GPQA Diamond (Epoch AI run) | 93.4% | Not measured | Only Grok 4.5 measured |
| ARC-AGI | 87.2% | Not measured | Only Grok 4.5 measured |
| ARC-AGI-2 | 52.6% | Not measured | Only Grok 4.5 measured |
| SimpleBench | 70.0% | Not measured | Only Grok 4.5 measured |
| Chess puzzles | 35.0% | Not measured | Only Grok 4.5 measured |
| LMArena Text: hard prompts | 1462 | Not measured | Only Grok 4.5 measured |
| LMArena Text: expert | 1465 | Not measured | Only Grok 4.5 measured |
| LMArena Text: hard prompts in English | 1464 | Not measured | Only Grok 4.5 measured |
| LMArena Vision: diagrams | 1304 | Not measured | Only Grok 4.5 measured |
| LMArena Vision: homework | 1295 | Not measured | Only Grok 4.5 measured |
| Kagi LLM Benchmark | 83.5% | Not measured | Only Grok 4.5 measured |
| Neither model has a result on the other 6 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index01
| Benchmark | Grok 4.5 | Hy4 preview | Leader |
|---|---|---|---|
| OTIS Mock AIME | 97.8% | Not measured | Only Grok 4.5 measured |
| FrontierMath, tiers 1 to 3 | 57.2% | Not measured | Only Grok 4.5 measured |
| FrontierMath, tier 4 | 24.4% | Not measured | Only Grok 4.5 measured |
| ProofBench | 31.0% | 75.0% | Hy4 preview |
| LMArena Text: math | 1460 | Not measured | Only Grok 4.5 measured |
| LMArena Text: mathematical work | 1482 | Not measured | Only Grok 4.5 measured |
| Neither model has a result on the other 7 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Grok 4.5 | Hy4 preview | Leader |
|---|---|---|---|
| MMLU Pro | 89.2% | Not measured | Only Grok 4.5 measured |
| LegalBench (Vals AI) | 86.0% | 83.8% | Grok 4.5 |
| CorpFin (Vals AI) | 67.4% | Not measured | Only Grok 4.5 measured |
| TaxEval (Vals AI) | 71.7% | Not measured | Only Grok 4.5 measured |
| MortgageTax (Vals AI) | 61.8% | Not measured | Only Grok 4.5 measured |
| MedCode (Vals AI) | 43.3% | 43.3% | Grok 4.5 |
| SimpleQA Verified | 48.3% | Not measured | Only Grok 4.5 measured |
| LMArena Text: science | 1464 | Not measured | Only Grok 4.5 measured |
| LMArena Text: medicine and healthcare | 1440 | Not measured | Only Grok 4.5 measured |
| LMArena Text: legal and government | 1463 | Not measured | Only Grok 4.5 measured |
| LMArena Text: business and finance | 1441 | Not measured | Only Grok 4.5 measured |
| FACTS Benchmark Suite | 50.2% | Not measured | Only Grok 4.5 measured |
| Neither model has a result on the other 6 boards here | |||
Web designDirectional onlyPublic boards, shown as published, kept out of the index9 boards, none shared
| Benchmark | Grok 4.5 | Hy4 preview | Leader |
|---|---|---|---|
| Design Arena: websites | 1281 | Not measured | Only Grok 4.5 measured |
| Design Arena: UI components | 1279 | Not measured | Only Grok 4.5 measured |
| Design Arena: game dev | 1263 | Not measured | Only Grok 4.5 measured |
| Design Arena: data viz | 1266 | Not measured | Only Grok 4.5 measured |
| Design Arena: 3D | 1257 | Not measured | Only Grok 4.5 measured |
| Design Arena: all code categories | 1275 | Not measured | Only Grok 4.5 measured |
| Design Arena: SVG | 1215 | Not measured | Only Grok 4.5 measured |
| Design Arena: ASCII art | 1257 | Not measured | Only Grok 4.5 measured |
| LiveBench design | 78.1% | Not measured | Only Grok 4.5 measured |
GeneralLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Grok 4.5 | Hy4 preview | Leader |
|---|---|---|---|
| Vals Index | Not measured | 53.2% | Only Hy4 preview measured |
| LiveBench data analysis | 73.0% | Not measured | Only Grok 4.5 measured |
| Public Benefits Bench (Vals AI) | Not measured | 68.6% | Only Hy4 preview measured |
| SAGE (Vals AI) | 35.0% | Not measured | Only Grok 4.5 measured |
| MedScribe (Vals AI) | 86.9% | 83.6% | Grok 4.5 |
| Vals Multimodal Index | 63.4% | Not measured | Only Grok 4.5 measured |
| Long context reasoning (AA-LCR) | 79.3% | Not measured | Only Grok 4.5 measured |
| DTBench | 96.5% | Not measured | Only Grok 4.5 measured |
| LMCA | 45.2% | Not measured | Only Grok 4.5 measured |
| Surface Evolver Bench | 74.4% | Not measured | Only Grok 4.5 measured |
| Furniture assembly | 22.5% | Not measured | Only Grok 4.5 measured |
| LMArena Text | 1448 | Not measured | Only Grok 4.5 measured |
| LMArena Text: instruction following | 1445 | Not measured | Only Grok 4.5 measured |
| LMArena Text: creative writing | 1442 | Not measured | Only Grok 4.5 measured |
| LMArena Vision | 1287 | Not measured | Only Grok 4.5 measured |
| LMArena Text: English | 1453 | Not measured | Only Grok 4.5 measured |
| LMArena Text: non-English | 1440 | Not measured | Only Grok 4.5 measured |
| LMArena Text: Chinese | 1495 | Not measured | Only Grok 4.5 measured |
| LMArena Text: German | 1448 | Not measured | Only Grok 4.5 measured |
| LMArena Text: Japanese | 1430 | Not measured | Only Grok 4.5 measured |
| LMArena Text: Korean | 1406 | Not measured | Only Grok 4.5 measured |
| LMArena Text: French | 1457 | Not measured | Only Grok 4.5 measured |
| LMArena Text: Spanish | 1451 | Not measured | Only Grok 4.5 measured |
| LMArena Text: Russian | 1449 | Not measured | Only Grok 4.5 measured |
| LMArena Text: Polish | 1432 | Not measured | Only Grok 4.5 measured |
| LMArena Text: multi-turn | 1456 | Not measured | Only Grok 4.5 measured |
| LMArena Text: longer queries | 1462 | Not measured | Only Grok 4.5 measured |
| LMArena Text: writing and language | 1445 | Not measured | Only Grok 4.5 measured |
| LMArena Text: entertainment and media | 1434 | Not measured | Only Grok 4.5 measured |
| LMArena Vision: English | 1285 | Not measured | Only Grok 4.5 measured |
| LMArena Vision: Chinese | 1345 | Not measured | Only Grok 4.5 measured |
| LMArena Vision: reading text | 1293 | Not measured | Only Grok 4.5 measured |
| LMArena Vision: humor | 1276 | Not measured | Only Grok 4.5 measured |
| LMArena Vision: creative writing | 1293 | Not measured | Only Grok 4.5 measured |
| LMArena Document | 1452 | Not measured | Only Grok 4.5 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 | Grok 4.5 | Hy4 preview | 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
Hy4 preview costs less
Repository review
50K input + 3K output tokens
Hy4 preview costs less
Agent loop
200K input + 10K output tokens
Hy4 preview 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 | SpaceXAI Grok 4.5 | Tencent Hy4 preview |
|---|---|---|
| Maker | xAI | Tencent |
| Weights | No public weights listed | Open weights |
| Released | July 8, 2026 | August 28, 2026 |
| Context window | 500K | 1.05M |
| Input $/Mtok | $2.00 | $0.7506 |
| Output $/Mtok | $6.00 | $2.2509 |
| Coding index | 58.6 | 44.3 |
| Independent measurements behind it | 6 | 3 |
| Cost per solved task | $0.62 | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Grok 4.5 better than Hy4 preview for coding?
Pick Grok 4.5 for coding: it scores 58.6 on the Vibe Coding Index against 44.3 for Hy4 preview. Pick Hy4 preview for output tokens 2.7x cheaper ($2.2509 vs $6.00 per million) and a larger context window (1.05M against 500K tokens).
Which is cheaper, Grok 4.5 or Hy4 preview?
Grok 4.5 costs $2.00 per million input tokens and $6.00 per million output tokens; Hy4 preview costs $0.7506 and $2.2509. Cost per solved task is known for Grok 4.5 only.
Which has the bigger context window, Grok 4.5 or Hy4 preview?
Hy4 preview, with 1.05M tokens against 500K.
How many benchmarks is the Grok 4.5 vs Hy4 preview comparison based on?
19 benchmarks have a result for both models as of October 21, 2026. Grok 4.5's coding index rests on 6 independent benchmarks and Hy4 preview's on 3. Where only one model has a result, the page says so instead of naming a winner.