Model comparison
Sonar vs Step 5 Preview
Step 5 Preview is the stronger model overall, scoring 43.8 to 37.8 on the Noometry Index.
Last verified . 0 shared benchmarks.
Perplexity
StepFunSummary
- The widest gap is in reasoning, where Step 5 Preview leads 38.0 to 20.3.
- Sonar is cheaper at $1 / $1 per million input/output tokens, against $1 / $2.70 for Step 5 Preview.
- Step 5 Preview accepts more context: 1.02M tokens versus 128K.
Side by side
| Sonar | Step 5 Preview | |
|---|---|---|
| Provider | Perplexity | StepFun |
| Noometry Index | 37.8 | 43.8 |
| Released | 2024-01-01 | 2026-09-16 |
| Weights | Proprietary | Proprietary |
| Context window | 128K | 1.02M |
| Max output | 4K | 66K |
| Input $ / M tokens | $1 | $1 |
| Output $ / M tokens | $1 | $2.70 |
| Results tracked | 7 | 3 |
Sponsored placements are available on pages like this one. Advertise on Noometry
Category by category
Coding Step 5 Preview leads
Sonar: 35.1 (#217), Step 5 Preview: 50.6 (#40)
| Benchmark | Sonar | Step 5 Preview |
|---|---|---|
| LMArena WebDev | — | 1569 |
| SciCode | — | 58.9% |
| LiveBench Coding | 35.1% | — |
Reasoning Step 5 Preview leads
Sonar: 20.3 (#221), Step 5 Preview: 38.0 (#58)
| Benchmark | Sonar | Step 5 Preview |
|---|---|---|
| CritPt | — | 20.9% |
| LiveBench Reasoning | 46.3% | — |
| LiveBench Data Analysis | 37.9% | — |
| LiveBench | 46.9% | — |
Math Not comparable
Sonar: 31.3 (#197), Step 5 Preview: —
| Benchmark | Sonar | Step 5 Preview |
|---|---|---|
| LiveBench Math | 41.6% | — |
Instruction Following Not comparable
Sonar: 71.5 (#146), Step 5 Preview: —
| Benchmark | Sonar | Step 5 Preview |
|---|---|---|
| LiveBench Instruction Following | 76.2% | — |
Writing & Preference Not comparable
Sonar: 52.6 (#166), Step 5 Preview: —
| Benchmark | Sonar | Step 5 Preview |
|---|---|---|
| LiveBench Language | 44.1% | — |
Frequently asked questions
Is Sonar better than Step 5 Preview?
Step 5 Preview is the stronger model overall, scoring 43.8 to 37.8 on the Noometry Index.
Which is cheaper, Sonar or Step 5 Preview?
Sonar is cheaper. It lists at $1 per million input tokens and $1 per million output tokens; Step 5 Preview lists at $1 and $2.70.
Is Sonar or Step 5 Preview better for coding?
Step 5 Preview scores higher on coding benchmarks: 50.6 versus 35.1 in the Noometry coding category.
Which has the bigger context window?
Step 5 Preview does, with 1.02M tokens against 128K.
How many benchmarks do Sonar and Step 5 Preview share?
0 benchmarks have published results for both models. Sonar has 7 scored results on Noometry and Step 5 Preview has 3.