Step 5 Preview vs Hy4 preview
Updated October 21, 2026. 16 benchmarks have a result for both. Coding is ranked on the Vibe Coding Index; every other board is shown as published.
Decision reading
Pick Step 5 Preview for coding: it scores 71.4 on the Vibe Coding Index against 61.6 for Hy4 preview.
Pick Hy4 preview when output tokens cost 1.1x less, or when what matters is LMArena WebDev or Vibe Code Bench (Vals AI), where it leads.
- Shared results
- 16
- Step 5 Preview only
- 45
- Hy4 preview only
- 8
- Like-for-like categories
- 4 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
Step 5 Preview
Step 5 Preview scores 71.4 against 61.6.
2 and 1 benchmarks behind the scores
Intelligence
AA Intelligence Index
No call
Only Step 5 Preview has a AA Intelligence Index result, 43.7.
Directional only
General
Vals Index
No call
Only Hy4 preview has a Vals Index result, 53.2%.
Directional only
Long documents
Listed context window
No call
Both take 1.05M tokens.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Hy4 preview
Step 5 Preview $0.0024, Hy4 preview $0.0021 per turn.
List prices
At a glance
- Coding index
- Step 5 Preview 71.4 from 2 benchmarks, Hy4 preview 61.6 from 1 benchmark.
- Widest category
- Math, 33.0 points apart on average over 1 shared benchmark.
- Widest single gap
- ProofBench: Step 5 Preview 42.0% against Hy4 preview 75.0%, 33.0 points apart on a 0 to 100 scale.
- Output price
- Step 5 Preview $2.70 against Hy4 preview $2.501 per million output tokens, 1.1x apart.
- Context window
- Both take 1.05M 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 | Step 5 Preview | Bars | Hy4 preview | Ties |
|---|---|---|---|---|
| Coding | 1 | 6 | ||
| Agentic work | 1 | 6 | ||
| Math | 0 | 1 | ||
| General | 0 | 1 | ||
| All shared boards | 2 | 14 |
CodingLike-for-likeFour of these boards feed the Vibe Coding Index16
| Benchmark | Step 5 Preview | Hy4 preview | Leader |
|---|---|---|---|
| LiveBench coding | 85.6% | Not measured | Only Step 5 Preview measured |
| LMArena WebDev | 1567 | 1631 | Hy4 preview |
| Terminal-Bench 4 (Vals AI) | 31.8% | 8.1% | Step 5 Preview |
| Vibe Code Bench (Vals AI) | 70.4% | 77.5% | Hy4 preview |
| Code migration (Vals AI) | 39.0% | 47.4% | Hy4 preview |
| ProgramBench (Vals AI) | Not measured | 0.0% | Only Hy4 preview measured |
| IOI (Vals AI) | 38.1% | 59.3% | Hy4 preview |
| Terminal-Bench 2.1 (Vals AI) | Not measured | 55.1% | Only Hy4 preview measured |
| SWE-bench Multimodal (Vals AI) | 40.8% | Not measured | Only Step 5 Preview measured |
| CyberBench (Vals AI) | Not measured | 65.4% | Only Hy4 preview measured |
| SciCode | 58.9% | Not measured | Only Step 5 Preview measured |
| LMArena Text: coding | 1485 | Not measured | Only Step 5 Preview measured |
| LMArena Text: software and IT | 1473 | Not measured | Only Step 5 Preview measured |
| LMArena WebDev: React | 1583 | 1653 | Hy4 preview |
| LMArena WebDev: HTML | 1556 | 1620 | Hy4 preview |
| LMArena WebDev: from an image | 1550 | Not measured | Only Step 5 Preview measured |
| Neither model has a result on the other 22 boards here | |||
IntelligenceDirectional onlyPublic boards, shown as published, kept out of the index1 board, none shared
| Benchmark | Step 5 Preview | Hy4 preview | Leader |
|---|---|---|---|
| AA Intelligence Index | 43.7 | Not measured | Only Step 5 Preview measured |
| Neither model has a result on the other 1 board here | |||
Agentic workLike-for-likePublic boards, shown as published, kept out of the index16
| Benchmark | Step 5 Preview | Hy4 preview | Leader |
|---|---|---|---|
| LiveBench research | 72.8% | Not measured | Only Step 5 Preview measured |
| LiveBench browser | 24.0% | Not measured | Only Step 5 Preview measured |
| LiveBench long agentic | 27.5% | Not measured | Only Step 5 Preview measured |
| SREBench (Vals AI) | 0.4% | 2.3% | Hy4 preview |
| Finance Agent (Vals AI) | 50.7% | 55.1% | Hy4 preview |
| Tax Agent Bench (Vals AI) | 27.3% | 32.6% | Hy4 preview |
| Legal Research Bench (Vals AI) | 40.4% | 45.2% | Hy4 preview |
| Harvey's Legal Agent Benchmark (Vals AI) | Not measured | 8.8% | Only Hy4 preview measured |
| Excel Modeling Benchmark (Vals AI) | 57.1% | 58.1% | Hy4 preview |
| BioMysteryBench (Vals AI) | 67.4% | 69.3% | Hy4 preview |
| Terminal-Bench-Science (Vals AI) | 2.9% | 1.4% | Step 5 Preview |
| Vals Science Index | 29.6% | Not measured | Only Step 5 Preview measured |
| Neither model has a result on the other 27 boards here | |||
ReasoningDirectional onlyPublic boards, shown as published, kept out of the index8 boards, none shared
| Benchmark | Step 5 Preview | Hy4 preview | Leader |
|---|---|---|---|
| LiveBench reasoning | 83.8% | Not measured | Only Step 5 Preview measured |
| MysteryMechanism (Vals AI) | 18.5% | Not measured | Only Step 5 Preview measured |
| Humanity's Last Exam (Artificial Analysis run) | 46.5% | Not measured | Only Step 5 Preview measured |
| LMArena Text: hard prompts | 1461 | Not measured | Only Step 5 Preview measured |
| LMArena Text: expert | 1485 | Not measured | Only Step 5 Preview measured |
| LMArena Text: hard prompts in English | 1454 | Not measured | Only Step 5 Preview measured |
| LMArena Vision: diagrams | 1308 | Not measured | Only Step 5 Preview measured |
| LMArena Vision: homework | 1265 | Not measured | Only Step 5 Preview measured |
| Neither model has a result on the other 13 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index01
| Benchmark | Step 5 Preview | Hy4 preview | Leader |
|---|---|---|---|
| ProofBench | 42.0% | 75.0% | Hy4 preview |
| LMArena Text: math | 1458 | Not measured | Only Step 5 Preview measured |
| LMArena Text: mathematical work | 1460 | Not measured | Only Step 5 Preview measured |
| Neither model has a result on the other 10 boards here | |||
KnowledgeDirectional onlyPublic boards, shown as published, kept out of the index6 boards, none shared
| Benchmark | Step 5 Preview | Hy4 preview | Leader |
|---|---|---|---|
| LegalBench (Vals AI) | Not measured | 83.8% | Only Hy4 preview measured |
| MedCode (Vals AI) | Not measured | 43.3% | Only Hy4 preview measured |
| LMArena Text: science | 1454 | Not measured | Only Step 5 Preview measured |
| LMArena Text: medicine and healthcare | 1439 | Not measured | Only Step 5 Preview measured |
| LMArena Text: legal and government | 1437 | Not measured | Only Step 5 Preview measured |
| LMArena Text: business and finance | 1435 | Not measured | Only Step 5 Preview measured |
| Neither model has a result on the other 11 boards here | |||
Web designDirectional onlyPublic boards, shown as published, kept out of the index1 board, none shared
| Benchmark | Step 5 Preview | Hy4 preview | Leader |
|---|---|---|---|
| LiveBench design | 76.9% | Not measured | Only Step 5 Preview measured |
| Neither model has a result on the other 8 boards here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index01
| Benchmark | Step 5 Preview | Hy4 preview | Leader |
|---|---|---|---|
| Vals Index | Not measured | 53.2% | Only Hy4 preview measured |
| LiveBench data analysis | 63.5% | Not measured | Only Step 5 Preview measured |
| Public Benefits Bench (Vals AI) | 58.1% | 68.6% | Hy4 preview |
| MedScribe (Vals AI) | Not measured | 83.6% | Only Hy4 preview measured |
| Long context reasoning (AA-LCR) | 88.3% | Not measured | Only Step 5 Preview measured |
| LMArena Text | 1440 | Not measured | Only Step 5 Preview measured |
| LMArena Text: instruction following | 1438 | Not measured | Only Step 5 Preview measured |
| LMArena Text: creative writing | 1409 | Not measured | Only Step 5 Preview measured |
| LMArena Vision | 1265 | Not measured | Only Step 5 Preview measured |
| LMArena Text: English | 1447 | Not measured | Only Step 5 Preview measured |
| LMArena Text: non-English | 1428 | Not measured | Only Step 5 Preview measured |
| LMArena Text: Chinese | 1500 | Not measured | Only Step 5 Preview measured |
| LMArena Text: Japanese | 1383 | Not measured | Only Step 5 Preview measured |
| LMArena Text: French | 1438 | Not measured | Only Step 5 Preview measured |
| LMArena Text: Spanish | 1441 | Not measured | Only Step 5 Preview measured |
| LMArena Text: Russian | 1433 | Not measured | Only Step 5 Preview measured |
| LMArena Text: multi-turn | 1437 | Not measured | Only Step 5 Preview measured |
| LMArena Text: longer queries | 1449 | Not measured | Only Step 5 Preview measured |
| LMArena Text: writing and language | 1425 | Not measured | Only Step 5 Preview measured |
| LMArena Text: entertainment and media | 1412 | Not measured | Only Step 5 Preview measured |
| LMArena Vision: English | 1290 | Not measured | Only Step 5 Preview measured |
| LMArena Vision: reading text | 1282 | Not measured | Only Step 5 Preview measured |
| Neither model has a result on the other 24 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Step 5 Preview | 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 | StepFun Step 5 Preview | Tencent Hy4 preview |
|---|---|---|
| Maker | StepFun | Tencent |
| Weights | Open weights | Open weights |
| Released | October 8, 2026 | August 28, 2026 |
| Context window | 1.05M | 1.05M |
| Input $/Mtok | $1.00 | $0.834 |
| Output $/Mtok | $2.70 | $2.501 |
| Coding index | 71.4 | 61.6 |
| Independent measurements behind it | 2 | 1 |
| Cost per solved task | Not computable | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Step 5 Preview better than Hy4 preview for coding?
Pick Step 5 Preview for coding: it scores 71.4 on the Vibe Coding Index against 61.6 for Hy4 preview. Pick Hy4 preview when output tokens cost 1.1x less, or when what matters is LMArena WebDev or Vibe Code Bench (Vals AI), where it leads.
Which is cheaper, Step 5 Preview or Hy4 preview?
Step 5 Preview costs $1.00 per million input tokens and $2.70 per million output tokens; Hy4 preview costs $0.834 and $2.501. Cost per solved task is known for neither of them.
Which has the bigger context window, Step 5 Preview or Hy4 preview?
Neither: both take 1.05M tokens.
How many benchmarks is the Step 5 Preview vs Hy4 preview comparison based on?
16 benchmarks have a result for both models as of October 21, 2026. Step 5 Preview's coding index rests on 2 independent benchmarks and Hy4 preview's on 1. Where only one model has a result, the page says so instead of naming a winner.