# Phi 3 Mini 128k Instruct vs Step 3.5 Flash

> Step 3.5 Flash is the stronger model overall, scoring 41.7 to 29.1 on the Noometry Index.

- Canonical page: https://noometry.com/compare/phi-3-mini-128k-instruct-vs-step-3-5-flash
- Last updated: 2026-10-10
- Shared benchmarks: 17

## Summary

- They share 17 benchmarks with published results for both. Phi 3 Mini 128k Instruct scores higher in 0 categories and Step 3.5 Flash in 8 categories; 8 gaps are clear of the uncertainty.
- The widest gap is in writing & preference, where Step 3.5 Flash leads 59.0 to 27.3.

## Snapshot

| | Phi 3 Mini 128k Instruct | Step 3.5 Flash |
|---|---|---|
| Provider | Microsoft | StepFun |
| Noometry Index | 29.1 | 41.7 |
| Rank | 303 | 116 |
| Context | — | 256K |
| Input $/M | — | $0.10 |
| Output $/M | — | $0.30 |
| Weights | Open | Open |

## Coding

- Phi 3 Mini 128k Instruct: 28.3 (#307)
- Step 3.5 Flash: 41.7 (#106)

| Benchmark | Phi 3 Mini 128k Instruct | Step 3.5 Flash |
|---|---|---|
| LMArena Coding | 1040 | 1436 |
| BigCodeBench Instruct | 29.6% | — |
| BigCodeBench Complete | 40.6% | — |

## Reasoning

- Phi 3 Mini 128k Instruct: 18.7 (#254)
- Step 3.5 Flash: 21.2 (#202)

| Benchmark | Phi 3 Mini 128k Instruct | Step 3.5 Flash |
|---|---|---|
| LMArena Hard Prompts | 1028 | 1411 |
| NYT Connections (extended) | — | 28.4% |

## Math

- Phi 3 Mini 128k Instruct: 29.2 (#220)
- Step 3.5 Flash: 40.6 (#77)

| Benchmark | Phi 3 Mini 128k Instruct | Step 3.5 Flash |
|---|---|---|
| LMArena Math | 1089 | 1408 |
| MathArena Final-Answer Competitions | — | 66.8% |

## Knowledge

- Phi 3 Mini 128k Instruct: 26.3 (#251)
- Step 3.5 Flash: 39.0 (#127)

| Benchmark | Phi 3 Mini 128k Instruct | Step 3.5 Flash |
|---|---|---|
| LMArena Expert | 984 | 1422 |

## Multilingual

- Phi 3 Mini 128k Instruct: 25.4 (#280)
- Step 3.5 Flash: 50.7 (#115)

| Benchmark | Phi 3 Mini 128k Instruct | Step 3.5 Flash |
|---|---|---|
| LMArena Non-English | 1000 | 1386 |
| LMArena Chinese | 1016 | 1448 |
| LMArena French | 1038 | 1421 |
| LMArena German | 1006 | 1404 |
| LMArena Japanese | 899 | 1353 |
| LMArena Korean | 856 | 1350 |
| LMArena Russian | 1004 | 1385 |
| LMArena Spanish | 1058 | 1419 |

## Instruction Following

- Phi 3 Mini 128k Instruct: 52.1 (#289)
- Step 3.5 Flash: 73.3 (#119)

| Benchmark | Phi 3 Mini 128k Instruct | Step 3.5 Flash |
|---|---|---|
| LMArena Instruction Following | 1023 | 1385 |

## Long Context

- Phi 3 Mini 128k Instruct: 30.3 (#284)
- Step 3.5 Flash: 42.8 (#112)

| Benchmark | Phi 3 Mini 128k Instruct | Step 3.5 Flash |
|---|---|---|
| LMArena Longer Query | 996 | 1402 |

## Writing & Preference

- Phi 3 Mini 128k Instruct: 27.3 (#296)
- Step 3.5 Flash: 59.0 (#108)

| Benchmark | Phi 3 Mini 128k Instruct | Step 3.5 Flash |
|---|---|---|
| LMArena Text | 1050 | 1403 |
| LMArena Creative Writing | 1024 | 1357 |
| LMArena Multi-Turn | 989 | 1405 |

## FAQ

### Is Phi 3 Mini 128k Instruct better than Step 3.5 Flash?

Step 3.5 Flash is the stronger model overall, scoring 41.7 to 29.1 on the Noometry Index.

### Is Phi 3 Mini 128k Instruct or Step 3.5 Flash better for coding?

Step 3.5 Flash scores higher on coding benchmarks: 41.7 versus 28.3 in the Noometry coding category.

### How many benchmarks do Phi 3 Mini 128k Instruct and Step 3.5 Flash share?

17 benchmarks have published results for both models. Phi 3 Mini 128k Instruct has 19 scored results on Noometry and Step 3.5 Flash has 19.