Model comparison
ERNIE 5.1 vs Grok 4 Fast
ERNIE 5.1 is the stronger model overall, scoring 43.1 to 39.0 on the Noometry Index.
Last verified . 18 shared benchmarks.
BaiduSummary
- They share 18 benchmarks with published results for both. ERNIE 5.1 scores higher in 6 categories and Grok 4 Fast in 2 categories; 8 gaps are clear of the uncertainty.
- The widest gap is in long context, where Grok 4 Fast leads 63.2 to 44.7.
Side by side
| ERNIE 5.1 | Grok 4 Fast | |
|---|---|---|
| Provider | Baidu | xAI |
| Noometry Index | 43.1 | 39.0 |
| Released | — | 2025-09-19 |
| Weights | Proprietary | Proprietary |
| Context window | — | — |
| Max output | — | — |
| Input $ / M tokens | — | — |
| Output $ / M tokens | — | — |
| Results tracked | 19 | 30 |
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Category by category
Coding ERNIE 5.1 leads
ERNIE 5.1: 43.4 (#78), Grok 4 Fast: 32.3 (#264)
| Benchmark | ERNIE 5.1 | Grok 4 Fast |
|---|---|---|
| LMArena Coding | 1488 | 1429 |
| LMArena WebDev | — | 1160 |
| WeirdML | — | 42.9% |
Agentic & Tool Use Not comparable
ERNIE 5.1: —, Grok 4 Fast: 29.3 (#80)
| Benchmark | ERNIE 5.1 | Grok 4 Fast |
|---|---|---|
| LMArena Search | 1227 | 1171 |
| τ²-bench Banking | — | 15.7% |
| Cybench | — | 30% |
Reasoning Grok 4 Fast leads
ERNIE 5.1: 20.9 (#209), Grok 4 Fast: 22.5 (#179)
| Benchmark | ERNIE 5.1 | Grok 4 Fast |
|---|---|---|
| LMArena Hard Prompts | 1481 | 1413 |
| ARC-AGI-2 | — | 5.3% |
| Kagi LLM Benchmark | — | 66.1% |
| NYT Connections (extended) | 23.4% | — |
| ARC-AGI-1 | — | 48.5% |
| DTBench | — | 82.7% |
| Epoch Capabilities Index | — | 144.21 |
| ForecastBench | — | 60.5 |
Math ERNIE 5.1 leads
ERNIE 5.1: 37.5 (#96), Grok 4 Fast: 36.1 (#126)
| Benchmark | ERNIE 5.1 | Grok 4 Fast |
|---|---|---|
| LMArena Math | 1481 | 1419 |
Knowledge ERNIE 5.1 leads
ERNIE 5.1: 41.2 (#103), Grok 4 Fast: 31.5 (#211)
| Benchmark | ERNIE 5.1 | Grok 4 Fast |
|---|---|---|
| LMArena Expert | 1491 | 1411 |
| Vectara Hallucination Rate | — | 19.7% |
Multilingual ERNIE 5.1 leads
ERNIE 5.1: 55.7 (#28), Grok 4 Fast: 51.5 (#106)
| Benchmark | ERNIE 5.1 | Grok 4 Fast |
|---|---|---|
| LMArena Non-English | 1455 | 1397 |
| LMArena Chinese | 1507 | 1458 |
| LMArena French | 1486 | 1433 |
| LMArena German | 1470 | 1383 |
| LMArena Japanese | 1422 | 1358 |
| LMArena Korean | 1428 | 1359 |
| LMArena Russian | 1459 | 1387 |
| LMArena Spanish | 1472 | 1414 |
Instruction Following ERNIE 5.1 leads
ERNIE 5.1: 76.9 (#35), Grok 4 Fast: 73.4 (#116)
| Benchmark | ERNIE 5.1 | Grok 4 Fast |
|---|---|---|
| LMArena Instruction Following | 1460 | 1388 |
Long Context Grok 4 Fast leads
ERNIE 5.1: 44.7 (#56), Grok 4 Fast: 63.2 (#3)
| Benchmark | ERNIE 5.1 | Grok 4 Fast |
|---|---|---|
| LMArena Longer Query | 1462 | 1415 |
| Fiction.LiveBench | — | 94.4% |
Writing & Preference ERNIE 5.1 leads
ERNIE 5.1: 65.3 (#50), Grok 4 Fast: 60.2 (#96)
| Benchmark | ERNIE 5.1 | Grok 4 Fast |
|---|---|---|
| LMArena Text | 1468 | 1407 |
| LMArena Creative Writing | 1440 | 1388 |
| LMArena Multi-Turn | 1471 | 1414 |
Frequently asked questions
Is ERNIE 5.1 better than Grok 4 Fast?
ERNIE 5.1 is the stronger model overall, scoring 43.1 to 39.0 on the Noometry Index.
Is ERNIE 5.1 or Grok 4 Fast better for coding?
ERNIE 5.1 scores higher on coding benchmarks: 43.4 versus 32.3 in the Noometry coding category.
How many benchmarks do ERNIE 5.1 and Grok 4 Fast share?
18 benchmarks have published results for both models. ERNIE 5.1 has 19 scored results on Noometry and Grok 4 Fast has 30.