# Grok 4.20 Multi-Agent vs Step 3.5 Flash

> Grok 4.20 Multi-Agent is the stronger model overall, scoring 46.2 to 42.3 on the Noometry Index. Step 3.5 Flash costs 10× less per token, which makes it the better buy when Grok 4.20 Multi-Agent's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/grok-4-20-multi-agent-vs-step-3-5-flash
- Last updated: 2026-10-10
- Shared benchmarks: 18

## Summary

- They share 18 benchmarks with published results for both. Grok 4.20 Multi-Agent scores higher in 7 categories and Step 3.5 Flash in 1 category; 5 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where Grok 4.20 Multi-Agent leads 43.9 to 22.2.
- The biggest single-benchmark swing is NYT Connections (extended): 89.6% for Grok 4.20 Multi-Agent and 28.4% for Step 3.5 Flash.
- Step 3.5 Flash is cheaper at $0.10 / $0.30 per million input/output tokens, against $1.25 / $2.50 for Grok 4.20 Multi-Agent.
- Grok 4.20 Multi-Agent accepts more context: 1M tokens versus 256K.
- Step 3.5 Flash has downloadable open weights; the other is API-only.

## Snapshot

| | Grok 4.20 Multi-Agent | Step 3.5 Flash |
|---|---|---|
| Provider | xAI | StepFun |
| Noometry Index | 46.2 | 42.3 |
| Rank | 65 | 116 |
| Context | 1M | 256K |
| Input $/M | $1.25 | $0.10 |
| Output $/M | $2.50 | $0.30 |
| Weights | Proprietary | Open |

## Coding

- Grok 4.20 Multi-Agent: 43.0 (#92)
- Step 3.5 Flash: 42.4 (#105)

| Benchmark | Grok 4.20 Multi-Agent | Step 3.5 Flash |
|---|---|---|
| LMArena Coding | 1457 | 1436 |

## Agentic & Tool Use

- Grok 4.20 Multi-Agent: —
- Step 3.5 Flash: —

| Benchmark | Grok 4.20 Multi-Agent | Step 3.5 Flash |
|---|---|---|
| LMArena Search | 1204 | — |

## Reasoning

- Grok 4.20 Multi-Agent: 43.9 (#48)
- Step 3.5 Flash: 22.2 (#202)

| Benchmark | Grok 4.20 Multi-Agent | Step 3.5 Flash |
|---|---|---|
| NYT Connections (extended) | 89.6% | 28.4% |
| LMArena Hard Prompts | 1448 | 1411 |

## Math

- Grok 4.20 Multi-Agent: 39.4 (#104)
- Step 3.5 Flash: 42.6 (#84)

| Benchmark | Grok 4.20 Multi-Agent | Step 3.5 Flash |
|---|---|---|
| LMArena Math | 1442 | 1408 |
| MathArena Final-Answer Competitions | — | 66.8% |

## Knowledge

- Grok 4.20 Multi-Agent: 40.4 (#119)
- Step 3.5 Flash: 39.6 (#132)

| Benchmark | Grok 4.20 Multi-Agent | Step 3.5 Flash |
|---|---|---|
| LMArena Expert | 1445 | 1421 |

## Multimodal

- Grok 4.20 Multi-Agent: 40.5 (#48)
- Step 3.5 Flash: —

| Benchmark | Grok 4.20 Multi-Agent | Step 3.5 Flash |
|---|---|---|
| LMArena Vision | 1259 | — |

## Multilingual

- Grok 4.20 Multi-Agent: 54.4 (#43)
- Step 3.5 Flash: 50.5 (#119)

| Benchmark | Grok 4.20 Multi-Agent | Step 3.5 Flash |
|---|---|---|
| LMArena Non-English | 1440 | 1385 |
| LMArena Chinese | 1475 | 1447 |
| LMArena French | 1466 | 1421 |
| LMArena German | 1456 | 1405 |
| LMArena Japanese | 1405 | 1354 |
| LMArena Korean | 1416 | 1352 |
| LMArena Russian | 1457 | 1385 |
| LMArena Spanish | 1447 | 1419 |

## Instruction Following

- Grok 4.20 Multi-Agent: 74.8 (#84)
- Step 3.5 Flash: 73.1 (#124)

| Benchmark | Grok 4.20 Multi-Agent | Step 3.5 Flash |
|---|---|---|
| LMArena Instruction Following | 1420 | 1385 |

## Long Context

- Grok 4.20 Multi-Agent: 43.7 (#88)
- Step 3.5 Flash: 42.8 (#117)

| Benchmark | Grok 4.20 Multi-Agent | Step 3.5 Flash |
|---|---|---|
| LMArena Longer Query | 1431 | 1402 |

## Writing & Preference

- Grok 4.20 Multi-Agent: 64.0 (#59)
- Step 3.5 Flash: 58.8 (#113)

| Benchmark | Grok 4.20 Multi-Agent | Step 3.5 Flash |
|---|---|---|
| LMArena Text | 1450 | 1403 |
| LMArena Creative Writing | 1436 | 1357 |
| LMArena Multi-Turn | 1452 | 1405 |

## FAQ

### Is Grok 4.20 Multi-Agent better than Step 3.5 Flash?

Grok 4.20 Multi-Agent is the stronger model overall, scoring 46.2 to 42.3 on the Noometry Index. Step 3.5 Flash costs 10× less per token, which makes it the better buy when Grok 4.20 Multi-Agent's lead doesn't matter for your workload.

### Which is cheaper, Grok 4.20 Multi-Agent or Step 3.5 Flash?

Step 3.5 Flash is cheaper. It lists at $0.10 per million input tokens and $0.30 per million output tokens; Grok 4.20 Multi-Agent lists at $1.25 and $2.50.

### Is Grok 4.20 Multi-Agent or Step 3.5 Flash better for coding?

They score almost the same on coding (43.0 vs 42.4); test both on your own repository before choosing.

### Which has the bigger context window?

Grok 4.20 Multi-Agent does, with 1M tokens against 256K.

### How many benchmarks do Grok 4.20 Multi-Agent and Step 3.5 Flash share?

18 benchmarks have published results for both models. Grok 4.20 Multi-Agent has 20 scored results on Noometry and Step 3.5 Flash has 19.