Model comparison
Step 3.7 Flash vs Step 5 Preview
Step 5 Preview is the stronger model overall, scoring 43.8 to 36.5 on the Noometry Index. Step 3.7 Flash costs 3.4× less per token, which makes it the better buy when Step 5 Preview's lead doesn't matter for your workload.
Last verified . 2 shared benchmarks.
StepFunSummary
- They share 2 benchmarks with published results for both. Step 3.7 Flash scores higher in 0 categories and Step 5 Preview in 2 categories; 2 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where Step 5 Preview leads 38.0 to 20.9.
- The biggest single-benchmark swing is SciCode: 40% for Step 3.7 Flash and 58.9% for Step 5 Preview.
- Step 3.7 Flash is cheaper at $0.18 / $1.11 per million input/output tokens, against $1 / $2.70 for Step 5 Preview.
- Step 5 Preview accepts more context: 1.02M tokens versus 256K.
- Step 3.7 Flash has downloadable open weights; the other is API-only.
Side by side
| Step 3.7 Flash | Step 5 Preview | |
|---|---|---|
| Provider | StepFun | StepFun |
| Noometry Index | 36.5 | 43.8 |
| Released | 2026-05-29 | 2026-09-16 |
| Weights | Open | Proprietary |
| Context window | 256K | 1.02M |
| Max output | 256K | 66K |
| Input $ / M tokens | $0.18 | $1 |
| Output $ / M tokens | $1.11 | $2.70 |
| Results tracked | 5 | 3 |
Sponsored placements are available on pages like this one. Advertise on Noometry
Category by category
Coding Step 5 Preview leads
Step 3.7 Flash: 39.4 (#147), Step 5 Preview: 50.6 (#40)
| Benchmark | Step 3.7 Flash | Step 5 Preview |
|---|---|---|
| SciCode | 40% | 58.9% |
| LMArena WebDev | — | 1569 |
| ALE-Bench | 694.12 | — |
Reasoning Step 5 Preview leads
Step 3.7 Flash: 20.9 (#211), Step 5 Preview: 38.0 (#58)
| Benchmark | Step 3.7 Flash | Step 5 Preview |
|---|---|---|
| CritPt | 2.3% | 20.9% |
| NYT Connections (extended) | 39.7% | — |
Math Not comparable
Step 3.7 Flash: 40.9 (#74), Step 5 Preview: —
| Benchmark | Step 3.7 Flash | Step 5 Preview |
|---|---|---|
| MathArena Final-Answer Competitions | 68.5% | — |
Frequently asked questions
Is Step 3.7 Flash better than Step 5 Preview?
Step 5 Preview is the stronger model overall, scoring 43.8 to 36.5 on the Noometry Index. Step 3.7 Flash costs 3.4× less per token, which makes it the better buy when Step 5 Preview's lead doesn't matter for your workload.
Which is cheaper, Step 3.7 Flash or Step 5 Preview?
Step 3.7 Flash is cheaper. It lists at $0.18 per million input tokens and $1.11 per million output tokens; Step 5 Preview lists at $1 and $2.70.
Is Step 3.7 Flash or Step 5 Preview better for coding?
Step 5 Preview scores higher on coding benchmarks: 50.6 versus 39.4 in the Noometry coding category.
Which has the bigger context window?
Step 5 Preview does, with 1.02M tokens against 256K.
How many benchmarks do Step 3.7 Flash and Step 5 Preview share?
2 benchmarks have published results for both models. Step 3.7 Flash has 5 scored results on Noometry and Step 5 Preview has 3.