# Sonar vs Step 3.7 Flash

> Sonar is the stronger model overall, scoring 38.5 to 37.3 on the Noometry Index. Step 3.7 Flash costs 2.4× less per token, which makes it the better buy when Sonar's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/sonar-vs-step-3-7-flash
- Last updated: 2026-10-11
- Shared benchmarks: 0

## Summary

- The widest gap is in math, where Step 3.7 Flash leads 42.9 to 33.7.
- Step 3.7 Flash is cheaper at $0.18 / $1.11 per million input/output tokens, against $1 / $1 for Sonar.
- Step 3.7 Flash accepts more context: 256K tokens versus 128K.
- Step 3.7 Flash has downloadable open weights; the other is API-only.

## Snapshot

| | Sonar | Step 3.7 Flash |
|---|---|---|
| Provider | Perplexity | StepFun |
| Noometry Index | 38.5 | 37.3 |
| Rank | 187 | 207 |
| Context | 128K | 256K |
| Input $/M | $1 | $0.18 |
| Output $/M | $1 | $1.11 |
| Weights | Proprietary | Open |

## Coding

- Sonar: 35.7 (#221)
- Step 3.7 Flash: 40.0 (#150)

| Benchmark | Sonar | Step 3.7 Flash |
|---|---|---|
| SciCode | — | 40% |
| LiveBench Coding | 35.1% | — |
| ALE-Bench | — | 694.12 |

## Reasoning

- Sonar: 21.1 (#227)
- Step 3.7 Flash: 21.6 (#219)

| Benchmark | Sonar | Step 3.7 Flash |
|---|---|---|
| NYT Connections (extended) | — | 39.7% |
| CritPt | — | 2.3% |
| LiveBench Reasoning | 46.3% | — |
| LiveBench Data Analysis | 37.9% | — |
| LiveBench | 46.9% | — |

## Math

- Sonar: 33.7 (#200)
- Step 3.7 Flash: 42.9 (#82)

| Benchmark | Sonar | Step 3.7 Flash |
|---|---|---|
| MathArena Final-Answer Competitions | — | 68.5% |
| LiveBench Math | 41.6% | — |

## Instruction Following

- Sonar: 71.4 (#150)
- Step 3.7 Flash: —

| Benchmark | Sonar | Step 3.7 Flash |
|---|---|---|
| LiveBench Instruction Following | 76.2% | — |

## Writing & Preference

- Sonar: 52.6 (#167)
- Step 3.7 Flash: —

| Benchmark | Sonar | Step 3.7 Flash |
|---|---|---|
| LiveBench Language | 44.1% | — |

## FAQ

### Is Sonar better than Step 3.7 Flash?

Sonar is the stronger model overall, scoring 38.5 to 37.3 on the Noometry Index. Step 3.7 Flash costs 2.4× less per token, which makes it the better buy when Sonar's lead doesn't matter for your workload.

### Which is cheaper, Sonar or Step 3.7 Flash?

Step 3.7 Flash is cheaper. It lists at $0.18 per million input tokens and $1.11 per million output tokens; Sonar lists at $1 and $1.

### Is Sonar or Step 3.7 Flash better for coding?

Step 3.7 Flash scores higher on coding benchmarks: 40.0 versus 35.7 in the Noometry coding category.

### Which has the bigger context window?

Step 3.7 Flash does, with 256K tokens against 128K.

### How many benchmarks do Sonar and Step 3.7 Flash share?

0 benchmarks have published results for both models. Sonar has 7 scored results on Noometry and Step 3.7 Flash has 5.