# Granite 4.2 8B vs Grok 4.1 Fast

> Granite 4.2 8B and Grok 4.1 Fast score almost the same on the Noometry Index (40.5 vs 41.4), so choose on price, context window or the category you care about most.

- Canonical page: https://noometry.com/compare/granite-4-2-8b-vs-grok-4-1-fast
- Last updated: 2026-10-10
- Shared benchmarks: 11

## Summary

- They share 11 benchmarks with published results for both. Granite 4.2 8B scores higher in 2 categories and Grok 4.1 Fast in 5 categories; 7 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where Grok 4.1 Fast leads 43.4 to 26.6.
- Granite 4.2 8B is cheaper at $0.06 / $0.25 per million input/output tokens, against $0.20 / $0.50 for Grok 4.1 Fast.
- Granite 4.2 8B accepts more context: 131K tokens versus 128K.
- Granite 4.2 8B has downloadable open weights; the other is API-only.

## Snapshot

| | Granite 4.2 8B | Grok 4.1 Fast |
|---|---|---|
| Provider | IBM | xAI |
| Noometry Index | 40.5 | 41.4 |
| Rank | 148 | 136 |
| Context | 131K | 128K |
| Input $/M | $0.06 | $0.20 |
| Output $/M | $0.25 | $0.50 |
| Weights | Open | Proprietary |

## Coding

- Granite 4.2 8B: 40.5 (#137)
- Grok 4.1 Fast: 34.1 (#245)

| Benchmark | Granite 4.2 8B | Grok 4.1 Fast |
|---|---|---|
| LMArena Coding | 1380 | 1411 |
| LMArena WebDev | — | 1242 |
| ALE-Bench | — | 394.93 |

## Agentic & Tool Use

- Granite 4.2 8B: —
- Grok 4.1 Fast: 36.3 (#39)

| Benchmark | Granite 4.2 8B | Grok 4.1 Fast |
|---|---|---|
| Berkeley Function Calling Leaderboard | — | 69.6% |
| τ²-bench Banking | — | 13.1% |
| LMArena Search | — | 1171 |
| Vending-Bench 2 | — | 1,107 |

## Reasoning

- Granite 4.2 8B: 26.6 (#131)
- Grok 4.1 Fast: 43.4 (#49)

| Benchmark | Granite 4.2 8B | Grok 4.1 Fast |
|---|---|---|
| LMArena Hard Prompts | 1329 | 1407 |
| SimpleBench | — | 56% |
| NYT Connections (extended) | — | 87.4% |
| DTBench | — | 87.7% |
| ForecastBench | — | 61 |

## Math

- Granite 4.2 8B: —
- Grok 4.1 Fast: 31.9 (#221)

| Benchmark | Granite 4.2 8B | Grok 4.1 Fast |
|---|---|---|
| MathArena Final-Answer Competitions | — | 60.9% |
| ProofBench | — | 4% |
| LMArena Math | — | 1408 |

## Knowledge

- Granite 4.2 8B: 38.4 (#145)
- Grok 4.1 Fast: 33.1 (#207)

| Benchmark | Granite 4.2 8B | Grok 4.1 Fast |
|---|---|---|
| LMArena Expert | 1384 | 1399 |
| Vectara Hallucination Rate | — | 17.8% |

## Multimodal

- Granite 4.2 8B: —
- Grok 4.1 Fast: 37.0 (#76)

| Benchmark | Granite 4.2 8B | Grok 4.1 Fast |
|---|---|---|
| LMArena Vision | — | 1201 |

## Multilingual

- Granite 4.2 8B: 44.5 (#178)
- Grok 4.1 Fast: 51.0 (#114)

| Benchmark | Granite 4.2 8B | Grok 4.1 Fast |
|---|---|---|
| LMArena Non-English | 1302 | 1391 |
| LMArena Chinese | 1366 | 1441 |
| LMArena Russian | 1285 | 1387 |
| LMArena French | — | 1415 |
| LMArena German | — | 1404 |
| LMArena Japanese | — | 1349 |
| LMArena Korean | — | 1361 |
| LMArena Spanish | — | 1413 |

## Instruction Following

- Granite 4.2 8B: 68.7 (#184)
- Grok 4.1 Fast: 72.7 (#133)

| Benchmark | Granite 4.2 8B | Grok 4.1 Fast |
|---|---|---|
| LMArena Instruction Following | 1301 | 1376 |

## Long Context

- Granite 4.2 8B: 40.3 (#159)
- Grok 4.1 Fast: 42.4 (#126)

| Benchmark | Granite 4.2 8B | Grok 4.1 Fast |
|---|---|---|
| LMArena Longer Query | 1324 | 1390 |

## Writing & Preference

- Granite 4.2 8B: 49.6 (#189)
- Grok 4.1 Fast: 57.2 (#131)

| Benchmark | Granite 4.2 8B | Grok 4.1 Fast |
|---|---|---|
| LMArena Text | 1320 | 1408 |
| LMArena Creative Writing | 1236 | 1394 |
| LMArena Multi-Turn | 1301 | 1389 |
| EQ-Bench Creative Writing | — | 1327 |

## FAQ

### Is Granite 4.2 8B better than Grok 4.1 Fast?

Granite 4.2 8B and Grok 4.1 Fast score almost the same on the Noometry Index (40.5 vs 41.4), so choose on price, context window or the category you care about most.

### Which is cheaper, Granite 4.2 8B or Grok 4.1 Fast?

Granite 4.2 8B is cheaper. It lists at $0.06 per million input tokens and $0.25 per million output tokens; Grok 4.1 Fast lists at $0.20 and $0.50.

### Is Granite 4.2 8B or Grok 4.1 Fast better for coding?

Granite 4.2 8B scores higher on coding benchmarks: 40.5 versus 34.1 in the Noometry coding category.

### Which has the bigger context window?

Granite 4.2 8B does, with 131K tokens against 128K.

### How many benchmarks do Granite 4.2 8B and Grok 4.1 Fast share?

11 benchmarks have published results for both models. Granite 4.2 8B has 11 scored results on Noometry and Grok 4.1 Fast has 32.