Step 3.7 Flash vs Solar Mini 4
Updated October 21, 2026. 7 benchmarks have a result for both. Coding is ranked on the Vibe Coding Index; every other board is shown as published.
Decision reading
Neither model has a coding score yet, so the two cannot be ranked on coding.
Step 3.7 Flash has the edge where what matters is SciCode or AA Intelligence Index, where it leads.
- Shared results
- 7
- Step 3.7 Flash only
- 11
- Solar Mini 4 only
- 0
- Like-for-like categories
- 5 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, six public coding benchmarks
No call
Neither has a coding score yet.
One side not measured
Intelligence
AA Intelligence Index
Solar Mini 4
Solar Mini 4 leads, 24.1 against 19.5.
Same board, both measured
Web design
Design Arena: websites
Step 3.7 Flash
Step 3.7 Flash leads, 1196 against 1160.
Same board, both measured
Long documents
Listed context window
Solar Mini 4
Solar Mini 4 takes 524K tokens against 262K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Solar Mini 4
Step 3.7 Flash $0.0008, Solar Mini 4 $0.0001 per turn.
List prices
At a glance
- Coding index
- Step 3.7 Flash not benchmarked, Solar Mini 4 not benchmarked.
- Widest category
- General, 9.7 points apart on average over 1 shared benchmark.
- Widest single gap
- Long context reasoning (AA-LCR): Step 3.7 Flash 73.7% against Solar Mini 4 83.3%, 9.7 points apart on a 0 to 100 scale.
- Output price
- Step 3.7 Flash $1.15 against Solar Mini 4 $0.20 per million output tokens, 5.7x apart.
- Context window
- Step 3.7 Flash takes 262K tokens, Solar Mini 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 | Step 3.7 Flash | Bars | Solar Mini 4 | Ties |
|---|---|---|---|---|
| Coding | 0 | 1 | ||
| Intelligence | 0 | 1 | ||
| Reasoning | 0 | 1 | ||
| Web design | 3 | 0 | ||
| General | 0 | 1 | ||
| All shared boards | 3 | 4 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index01
| Benchmark | Step 3.7 Flash | Solar Mini 4 | Leader |
|---|---|---|---|
| AA Coding Index | 39.6 | Not measured | Only Step 3.7 Flash measured |
| SciCode | 43.9% | 47.6% | Solar Mini 4 |
| Terminal-Bench Hard (Artificial Analysis run) | 35.6% | Not measured | Only Step 3.7 Flash measured |
| ALE-Bench | 694.1 | Not measured | Only Step 3.7 Flash measured |
| Neither model has a result on the other 34 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index01
| Benchmark | Step 3.7 Flash | Solar Mini 4 | Leader |
|---|---|---|---|
| AA Intelligence Index | 19.5 | 24.1 | Solar Mini 4 |
| Neither model has a result on the other 1 board here | |||
Agentic workDirectional onlyPublic boards, shown as published, kept out of the index1 board, none shared
| Benchmark | Step 3.7 Flash | Solar Mini 4 | Leader |
|---|---|---|---|
| τ²-Bench Telecom | 98.5% | Not measured | Only Step 3.7 Flash measured |
| Neither model has a result on the other 38 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index01
| Benchmark | Step 3.7 Flash | Solar Mini 4 | Leader |
|---|---|---|---|
| GPQA Diamond (Artificial Analysis run) | 80.9% | Not measured | Only Step 3.7 Flash measured |
| Humanity's Last Exam (Artificial Analysis run) | 21.4% | 25.8% | Solar Mini 4 |
| Neither model has a result on the other 19 boards here | |||
MathNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Step 3.7 Flash | Solar Mini 4 | Leader |
|---|---|---|---|
| Neither model has a result on 13 boards here | |||
KnowledgeNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Step 3.7 Flash | Solar Mini 4 | Leader |
|---|---|---|---|
| Neither model has a result on 17 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index30
| Benchmark | Step 3.7 Flash | Solar Mini 4 | Leader |
|---|---|---|---|
| Design Arena: websites | 1196 | 1160 | Step 3.7 Flash |
| Design Arena: UI components | 1179 | Not measured | Only Step 3.7 Flash measured |
| Design Arena: game dev | 1158 | 1113 | Step 3.7 Flash |
| Design Arena: data viz | 1172 | Not measured | Only Step 3.7 Flash measured |
| Design Arena: 3D | 1129 | Not measured | Only Step 3.7 Flash measured |
| Design Arena: all code categories | 1182 | 1153 | Step 3.7 Flash |
| Design Arena: SVG | 1085 | Not measured | Only Step 3.7 Flash measured |
| Design Arena: ASCII art | 1152 | Not measured | Only Step 3.7 Flash measured |
| Neither model has a result on the other 1 board here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index01
| Benchmark | Step 3.7 Flash | Solar Mini 4 | Leader |
|---|---|---|---|
| IFBench | 67.3% | Not measured | Only Step 3.7 Flash measured |
| Long context reasoning (AA-LCR) | 73.7% | 83.3% | Solar Mini 4 |
| Neither model has a result on the other 44 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Step 3.7 Flash | Solar Mini 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 Mini 4 costs less
Repository review
50K input + 3K output tokens
Solar Mini 4 costs less
Agent loop
200K input + 10K output tokens
Solar Mini 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 | StepFun Step 3.7 Flash | Upstage Solar Mini 4 |
|---|---|---|
| Maker | StepFun | Upstage |
| Weights | Open weights | No public weights listed |
| Released | May 28, 2026 | September 23, 2026 |
| Context window | 262K | 524K |
| Input $/Mtok | $0.20 | $0.05 |
| Output $/Mtok | $1.15 | $0.20 |
| Coding index | Not benchmarked | Not benchmarked |
| Independent measurements behind it | 0 | 0 |
| Cost per solved task | Not computable | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Step 3.7 Flash better than Solar Mini 4 for coding?
Neither model has a coding score yet, so the two cannot be ranked on coding. Step 3.7 Flash has the edge where what matters is SciCode or AA Intelligence Index, where it leads.
Which is cheaper, Step 3.7 Flash or Solar Mini 4?
Step 3.7 Flash costs $0.20 per million input tokens and $1.15 per million output tokens; Solar Mini 4 costs $0.05 and $0.20. Cost per solved task is known for neither of them.
Which has the bigger context window, Step 3.7 Flash or Solar Mini 4?
Solar Mini 4, with 524K tokens against 262K.
How many benchmarks is the Step 3.7 Flash vs Solar Mini 4 comparison based on?
7 benchmarks have a result for both models as of October 21, 2026. Step 3.7 Flash's coding index rests on 0 independent benchmarks and Solar Mini 4's on 0. Where only one model has a result, the page says so instead of naming a winner.