Model comparison
ERNIE 5.1 vs Grok 4 Fast
ERNIE 5.1 is the stronger model overall, scoring 43.8 to 39.4 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; 7 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 | 43.8 | 39.4 |
| 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: 44.0 (#76), Grok 4 Fast: 32.5 (#271)
| Benchmark | ERNIE 5.1 | Grok 4 Fast |
|---|---|---|
| LMArena Coding | 1488 | 1429 |
| LMArena WebDev | — | 1159 |
| WeirdML | — | 42.9% |
Agentic & Tool Use Not comparable
ERNIE 5.1: —, Grok 4 Fast: 29.5 (#86)
| Benchmark | ERNIE 5.1 | Grok 4 Fast |
|---|---|---|
| LMArena Search | 1227 | 1171 |
| τ²-bench Banking | — | 15.7% |
| Cybench | — | 30% |
Reasoning Too close to call
ERNIE 5.1: 21.9 (#211), Grok 4 Fast: 22.2 (#201)
| Benchmark | ERNIE 5.1 | Grok 4 Fast |
|---|---|---|
| LMArena Hard Prompts | 1481 | 1412 |
| 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 | — | 144.2 |
| ForecastBench | — | 60.5 |
Math ERNIE 5.1 leads
ERNIE 5.1: 40.3 (#92), Grok 4 Fast: 38.9 (#123)
| Benchmark | ERNIE 5.1 | Grok 4 Fast |
|---|---|---|
| LMArena Math | 1481 | 1419 |
Knowledge ERNIE 5.1 leads
ERNIE 5.1: 41.9 (#102), Grok 4 Fast: 32.0 (#214)
| Benchmark | ERNIE 5.1 | Grok 4 Fast |
|---|---|---|
| LMArena Expert | 1492 | 1411 |
| Vectara Hallucination Rate | — | 19.7% |
Multilingual ERNIE 5.1 leads
ERNIE 5.1: 55.5 (#29), Grok 4 Fast: 51.3 (#111)
| Benchmark | ERNIE 5.1 | Grok 4 Fast |
|---|---|---|
| LMArena Non-English | 1454 | 1396 |
| LMArena Chinese | 1508 | 1457 |
| LMArena French | 1488 | 1431 |
| LMArena German | 1470 | 1383 |
| LMArena Japanese | 1422 | 1352 |
| LMArena Korean | 1427 | 1357 |
| LMArena Russian | 1459 | 1389 |
| LMArena Spanish | 1473 | 1415 |
Instruction Following ERNIE 5.1 leads
ERNIE 5.1: 76.7 (#37), Grok 4 Fast: 73.2 (#121)
| Benchmark | ERNIE 5.1 | Grok 4 Fast |
|---|---|---|
| LMArena Instruction Following | 1460 | 1387 |
Long Context Grok 4 Fast leads
ERNIE 5.1: 44.7 (#59), 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: 65.1 (#52), Grok 4 Fast: 60.0 (#102)
| Benchmark | ERNIE 5.1 | Grok 4 Fast |
|---|---|---|
| LMArena Text | 1468 | 1407 |
| LMArena Creative Writing | 1441 | 1387 |
| 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 43.8 to 39.4 on the Noometry Index.
Is ERNIE 5.1 or Grok 4 Fast better for coding?
ERNIE 5.1 scores higher on coding benchmarks: 44.0 versus 32.5 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.