Model comparison
Grok 4 Fast vs Sonar
Grok 4 Fast and Sonar score almost the same on the Noometry Index (39.4 vs 38.5), so choose on price, context window or the category you care about most.
Last verified . 0 shared benchmarks.
PerplexitySummary
- The widest gap is in writing & preference, where Grok 4 Fast leads 60.0 to 52.6.
Side by side
| Grok 4 Fast | Sonar | |
|---|---|---|
| Provider | xAI | Perplexity |
| Noometry Index | 39.4 | 38.5 |
| Released | 2025-09-19 | 2024-01-01 |
| Weights | Proprietary | Proprietary |
| Context window | — | 128K |
| Max output | — | 4K |
| Input $ / M tokens | — | $1 |
| Output $ / M tokens | — | $1 |
| Results tracked | 30 | 7 |
Sponsored placements are available on pages like this one. Advertise on Noometry
Category by category
Coding Sonar leads
Grok 4 Fast: 32.5 (#271), Sonar: 35.7 (#221)
| Benchmark | Grok 4 Fast | Sonar |
|---|---|---|
| LMArena WebDev | 1159 | — |
| WeirdML | 42.9% | — |
| LiveBench Coding | — | 35.1% |
| LMArena Coding | 1429 | — |
Agentic & Tool Use Not comparable
Grok 4 Fast: 29.5 (#86), Sonar: —
| Benchmark | Grok 4 Fast | Sonar |
|---|---|---|
| τ²-bench Banking | 15.7% | — |
| Cybench | 30% | — |
| LMArena Search | 1171 | — |
Reasoning Grok 4 Fast leads
Grok 4 Fast: 22.2 (#201), Sonar: 21.1 (#227)
| Benchmark | Grok 4 Fast | Sonar |
|---|---|---|
| ARC-AGI-2 | 5.3% | — |
| Kagi LLM Benchmark | 66.1% | — |
| ARC-AGI-1 | 48.5% | — |
| LiveBench Reasoning | — | 46.3% |
| LMArena Hard Prompts | 1412 | — |
| DTBench | 82.7% | — |
| LiveBench Data Analysis | — | 37.9% |
| Epoch Capabilities Index | 144.2 | — |
| ForecastBench | 60.5 | — |
| LiveBench | — | 46.9% |
Math Grok 4 Fast leads
Grok 4 Fast: 38.9 (#123), Sonar: 33.7 (#200)
| Benchmark | Grok 4 Fast | Sonar |
|---|---|---|
| LiveBench Math | — | 41.6% |
| LMArena Math | 1419 | — |
Knowledge Not comparable
Grok 4 Fast: 32.0 (#214), Sonar: —
| Benchmark | Grok 4 Fast | Sonar |
|---|---|---|
| Vectara Hallucination Rate | 19.7% | — |
| LMArena Expert | 1411 | — |
Multilingual Not comparable
Grok 4 Fast: 51.3 (#111), Sonar: —
| Benchmark | Grok 4 Fast | Sonar |
|---|---|---|
| LMArena Non-English | 1396 | — |
| LMArena Chinese | 1457 | — |
| LMArena French | 1431 | — |
| LMArena German | 1383 | — |
| LMArena Japanese | 1352 | — |
| LMArena Korean | 1357 | — |
| LMArena Russian | 1389 | — |
| LMArena Spanish | 1415 | — |
Instruction Following Grok 4 Fast leads
Grok 4 Fast: 73.2 (#121), Sonar: 71.4 (#150)
| Benchmark | Grok 4 Fast | Sonar |
|---|---|---|
| LiveBench Instruction Following | — | 76.2% |
| LMArena Instruction Following | 1387 | — |
Long Context Not comparable
Grok 4 Fast: 63.2 (#3), Sonar: —
| Benchmark | Grok 4 Fast | Sonar |
|---|---|---|
| Fiction.LiveBench | 94.4% | — |
| LMArena Longer Query | 1415 | — |
Writing & Preference Grok 4 Fast leads
Grok 4 Fast: 60.0 (#102), Sonar: 52.6 (#167)
| Benchmark | Grok 4 Fast | Sonar |
|---|---|---|
| LMArena Text | 1407 | — |
| LMArena Creative Writing | 1387 | — |
| LMArena Multi-Turn | 1414 | — |
| LiveBench Language | — | 44.1% |
Frequently asked questions
Is Grok 4 Fast better than Sonar?
Grok 4 Fast and Sonar score almost the same on the Noometry Index (39.4 vs 38.5), so choose on price, context window or the category you care about most.
Is Grok 4 Fast or Sonar better for coding?
Sonar scores higher on coding benchmarks: 35.7 versus 32.5 in the Noometry coding category.
How many benchmarks do Grok 4 Fast and Sonar share?
0 benchmarks have published results for both models. Grok 4 Fast has 30 scored results on Noometry and Sonar has 7.