Hy4 preview vs Solar Pro 4
Solar Pro 4 costs 4.2x less per output token than Hy4 preview ($0.60 vs $2.501 per million). Updated October 22, 2026; 3 benchmarks have a result for both.
Hy4 preview or Solar Pro 4: which to pick
Only Hy4 preview has a coding score, 44.3 on the Vibe Coding Index; Solar Pro 4 has none, so the two cannot be ranked on coding.
Pick Solar Pro 4 for output tokens 4.2x cheaper ($0.60 vs $2.501 per million).
- Shared results
- 3
- Hy4 preview only
- 21
- Solar Pro 4 only
- 42
- Like-for-like categories
- 1 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
No call
Only Hy4 preview has a coding score, so no call is made.
One side not measured
Intelligence
AA Intelligence Index
No call
Only Solar Pro 4 has a AA Intelligence Index result, 28.2.
Directional only
Web design
Design Arena: websites
No call
Only Solar Pro 4 has a Design Arena: websites result, 1176.
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 524K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Solar Pro 4
Hy4 preview $0.0021, Solar Pro 4 $0.0004 per turn.
List prices
At a glance
- Coding index
- Hy4 preview 44.3 from 3 benchmarks, Solar Pro 4 not benchmarked.
- Widest category
- Coding, 38.3 points apart on average over 3 shared benchmarks.
- Widest single gap
- LMArena WebDev: React: Hy4 preview 1653 against Solar Pro 4 1363, 39.5 points apart on a 0 to 100 scale.
- Output price
- Hy4 preview $2.501 against Solar Pro 4 $0.60 per million output tokens, 4.2x apart.
- Context window
- Hy4 preview takes 1.05M tokens, Solar Pro 4 524K.
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 | Hy4 preview | Bars | Solar Pro 4 | Ties |
|---|---|---|---|---|
| Coding | 3 | 0 | ||
| All shared boards | 3 | 0 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index30
| Benchmark | Hy4 preview | Solar Pro 4 | Leader |
|---|---|---|---|
| LMArena WebDev | 1631 | 1371 | Hy4 preview |
| AA Coding Index | Not measured | 52.7 | Only Solar Pro 4 measured |
| Terminal-Bench 4 (Vals AI) | 8.1% | Not measured | Only Hy4 preview measured |
| Vibe Code Bench (Vals AI) | 77.5% | Not measured | Only Hy4 preview measured |
| Code migration (Vals AI) | 47.4% | Not measured | Only Hy4 preview measured |
| ProgramBench (Vals AI) | 0.0% | Not measured | Only Hy4 preview measured |
| IOI (Vals AI) | 59.3% | Not measured | Only Hy4 preview measured |
| Terminal-Bench 2.1 (Vals AI) | 55.1% | Not measured | Only Hy4 preview measured |
| CyberBench (Vals AI) | 65.4% | Not measured | Only Hy4 preview measured |
| SciCode | Not measured | 48.0% | Only Solar Pro 4 measured |
| ALE-Bench | Not measured | 179.3 | Only Solar Pro 4 measured |
| LMArena Text: coding | Not measured | 1438 | Only Solar Pro 4 measured |
| LMArena Text: software and IT | Not measured | 1431 | Only Solar Pro 4 measured |
| LMArena WebDev: React | 1653 | 1363 | Hy4 preview |
| LMArena WebDev: HTML | 1620 | 1371 | Hy4 preview |
| Neither model has a result on the other 24 boards here | |||
IntelligenceDirectional onlyPublic boards, shown as published, kept out of the index1 board, none shared
| Benchmark | Hy4 preview | Solar Pro 4 | Leader |
|---|---|---|---|
| AA Intelligence Index | Not measured | 28.2 | Only Solar Pro 4 measured |
| Neither model has a result on the other 1 board here | |||
Agentic workDirectional onlyPublic boards, shown as published, kept out of the index9 boards, none shared
| Benchmark | Hy4 preview | Solar Pro 4 | Leader |
|---|---|---|---|
| Design Arena: agents building web apps | Not measured | 1105 | Only Solar Pro 4 measured |
| SREBench (Vals AI) | 2.3% | Not measured | Only Hy4 preview measured |
| Finance Agent (Vals AI) | 55.1% | Not measured | Only Hy4 preview measured |
| Tax Agent Bench (Vals AI) | 32.6% | Not measured | Only Hy4 preview measured |
| Legal Research Bench (Vals AI) | 45.2% | Not measured | Only Hy4 preview measured |
| Harvey's Legal Agent Benchmark (Vals AI) | 8.8% | Not measured | Only Hy4 preview measured |
| Excel Modeling Benchmark (Vals AI) | 58.1% | Not measured | Only Hy4 preview measured |
| BioMysteryBench (Vals AI) | 69.3% | Not measured | Only Hy4 preview measured |
| Terminal-Bench-Science (Vals AI) | 1.4% | Not measured | Only Hy4 preview measured |
| Neither model has a result on the other 32 boards here | |||
ReasoningDirectional onlyPublic boards, shown as published, kept out of the index5 boards, none shared
| Benchmark | Hy4 preview | Solar Pro 4 | Leader |
|---|---|---|---|
| GPQA Diamond (Artificial Analysis run) | Not measured | 89.1% | Only Solar Pro 4 measured |
| Humanity's Last Exam (Artificial Analysis run) | Not measured | 29.8% | Only Solar Pro 4 measured |
| LMArena Text: hard prompts | Not measured | 1400 | Only Solar Pro 4 measured |
| LMArena Text: expert | Not measured | 1428 | Only Solar Pro 4 measured |
| LMArena Text: hard prompts in English | Not measured | 1427 | Only Solar Pro 4 measured |
| Neither model has a result on the other 17 boards here | |||
MathDirectional onlyPublic boards, shown as published, kept out of the index3 boards, none shared
| Benchmark | Hy4 preview | Solar Pro 4 | Leader |
|---|---|---|---|
| ProofBench | 75.0% | Not measured | Only Hy4 preview measured |
| LMArena Text: math | Not measured | 1421 | Only Solar Pro 4 measured |
| LMArena Text: mathematical work | Not measured | 1427 | Only Solar Pro 4 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 | Hy4 preview | Solar Pro 4 | Leader |
|---|---|---|---|
| LegalBench (Vals AI) | 83.8% | Not measured | Only Hy4 preview measured |
| MedCode (Vals AI) | 43.3% | Not measured | Only Hy4 preview measured |
| LMArena Text: science | Not measured | 1404 | Only Solar Pro 4 measured |
| LMArena Text: medicine and healthcare | Not measured | 1374 | Only Solar Pro 4 measured |
| LMArena Text: legal and government | Not measured | 1383 | Only Solar Pro 4 measured |
| LMArena Text: business and finance | Not measured | 1381 | Only Solar Pro 4 measured |
| Neither model has a result on the other 12 boards here | |||
Web designDirectional onlyPublic boards, shown as published, kept out of the index6 boards, none shared
| Benchmark | Hy4 preview | Solar Pro 4 | Leader |
|---|---|---|---|
| Design Arena: websites | Not measured | 1176 | Only Solar Pro 4 measured |
| Design Arena: UI components | Not measured | 1147 | Only Solar Pro 4 measured |
| Design Arena: game dev | Not measured | 1169 | Only Solar Pro 4 measured |
| Design Arena: data viz | Not measured | 1177 | Only Solar Pro 4 measured |
| Design Arena: 3D | Not measured | 1178 | Only Solar Pro 4 measured |
| Design Arena: all code categories | Not measured | 1182 | Only Solar Pro 4 measured |
| Neither model has a result on the other 3 boards here | |||
GeneralDirectional onlyPublic boards, shown as published, kept out of the index21 boards, none shared
| Benchmark | Hy4 preview | Solar Pro 4 | Leader |
|---|---|---|---|
| Vals Index | 53.2% | Not measured | Only Hy4 preview measured |
| Public Benefits Bench (Vals AI) | 68.6% | Not measured | Only Hy4 preview measured |
| MedScribe (Vals AI) | 83.6% | Not measured | Only Hy4 preview measured |
| Long context reasoning (AA-LCR) | Not measured | 70.7% | Only Solar Pro 4 measured |
| LMArena Text | Not measured | 1388 | Only Solar Pro 4 measured |
| LMArena Text: instruction following | Not measured | 1375 | Only Solar Pro 4 measured |
| LMArena Text: creative writing | Not measured | 1317 | Only Solar Pro 4 measured |
| LMArena Text: English | Not measured | 1414 | Only Solar Pro 4 measured |
| LMArena Text: non-English | Not measured | 1363 | Only Solar Pro 4 measured |
| LMArena Text: Chinese | Not measured | 1422 | Only Solar Pro 4 measured |
| LMArena Text: German | Not measured | 1358 | Only Solar Pro 4 measured |
| LMArena Text: Japanese | Not measured | 1320 | Only Solar Pro 4 measured |
| LMArena Text: Korean | Not measured | 1383 | Only Solar Pro 4 measured |
| LMArena Text: French | Not measured | 1400 | Only Solar Pro 4 measured |
| LMArena Text: Spanish | Not measured | 1409 | Only Solar Pro 4 measured |
| LMArena Text: Russian | Not measured | 1357 | Only Solar Pro 4 measured |
| LMArena Text: Polish | Not measured | 1304 | Only Solar Pro 4 measured |
| LMArena Text: multi-turn | Not measured | 1385 | Only Solar Pro 4 measured |
| LMArena Text: longer queries | Not measured | 1382 | Only Solar Pro 4 measured |
| LMArena Text: writing and language | Not measured | 1344 | Only Solar Pro 4 measured |
| LMArena Text: entertainment and media | Not measured | 1332 | Only Solar Pro 4 measured |
| Neither model has a result on the other 25 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Hy4 preview | Solar Pro 4 | 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
Solar Pro 4 costs less
Repository review
50K input + 3K output tokens
Solar Pro 4 costs less
Agent loop
200K input + 10K output tokens
Solar Pro 4 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 | Tencent Hy4 preview | Upstage Solar Pro 4 |
|---|---|---|
| Maker | Tencent | Upstage |
| Weights | Open weights | No public weights listed |
| Released | August 28, 2026 | August 10, 2026 |
| Context window | 1.05M | 524K |
| Input $/Mtok | $0.834 | $0.15 |
| Output $/Mtok | $2.501 | $0.60 |
| Coding index | 44.3 | Not benchmarked |
| Independent measurements behind it | 3 | 1 |
| Cost per solved task | Not computable | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Hy4 preview better than Solar Pro 4 for coding?
Only Hy4 preview has a coding score, 44.3 on the Vibe Coding Index; Solar Pro 4 has none, so the two cannot be ranked on coding. Pick Solar Pro 4 for output tokens 4.2x cheaper ($0.60 vs $2.501 per million).
Which is cheaper, Hy4 preview or Solar Pro 4?
Hy4 preview costs $0.834 per million input tokens and $2.501 per million output tokens; Solar Pro 4 costs $0.15 and $0.60. Cost per solved task is known for neither of them.
Which has the bigger context window, Hy4 preview or Solar Pro 4?
Hy4 preview, with 1.05M tokens against 524K.
How many benchmarks is the Hy4 preview vs Solar Pro 4 comparison based on?
3 benchmarks have a result for both models as of October 22, 2026. Hy4 preview's coding index rests on 3 independent benchmarks and Solar Pro 4's on 1. Where only one model has a result, the page says so instead of naming a winner.