Model comparison
Grok 4.1 Fast vs Sonar
Grok 4.1 Fast is the stronger model overall, scoring 41.4 to 38.5 on the Noometry Index.
Last verified . 0 shared benchmarks.
PerplexitySummary
- The widest gap is in reasoning, where Grok 4.1 Fast leads 43.4 to 21.1.
- Grok 4.1 Fast is cheaper at $0.20 / $0.50 per million input/output tokens, against $1 / $1 for Sonar.
Side by side
| Grok 4.1 Fast | Sonar | |
|---|---|---|
| Provider | xAI | Perplexity |
| Noometry Index | 41.4 | 38.5 |
| Released | 2025-06-27 | 2024-01-01 |
| Weights | Proprietary | Proprietary |
| Context window | 128K | 128K |
| Max output | 30K | 4K |
| Input $ / M tokens | $0.20 | $1 |
| Output $ / M tokens | $0.50 | $1 |
| Results tracked | 32 | 7 |
Sponsored placements are available on pages like this one. Advertise on Noometry
Category by category
Coding Sonar leads
Grok 4.1 Fast: 34.1 (#245), Sonar: 35.7 (#221)
| Benchmark | Grok 4.1 Fast | Sonar |
|---|---|---|
| LMArena WebDev | 1242 | — |
| LiveBench Coding | — | 35.1% |
| LMArena Coding | 1411 | — |
| ALE-Bench | 394.93 | — |
Agentic & Tool Use Not comparable
Grok 4.1 Fast: 36.3 (#39), Sonar: —
| Benchmark | Grok 4.1 Fast | Sonar |
|---|---|---|
| Berkeley Function Calling Leaderboard | 69.6% | — |
| τ²-bench Banking | 13.1% | — |
| LMArena Search | 1171 | — |
| Vending-Bench 2 | 1,107 | — |
Reasoning Grok 4.1 Fast leads
Grok 4.1 Fast: 43.4 (#49), Sonar: 21.1 (#227)
| Benchmark | Grok 4.1 Fast | Sonar |
|---|---|---|
| SimpleBench | 56% | — |
| NYT Connections (extended) | 87.4% | — |
| LiveBench Reasoning | — | 46.3% |
| LMArena Hard Prompts | 1407 | — |
| DTBench | 87.7% | — |
| LiveBench Data Analysis | — | 37.9% |
| ForecastBench | 61 | — |
| LiveBench | — | 46.9% |
Math Sonar leads
Grok 4.1 Fast: 31.9 (#221), Sonar: 33.7 (#200)
| Benchmark | Grok 4.1 Fast | Sonar |
|---|---|---|
| MathArena Final-Answer Competitions | 60.9% | — |
| ProofBench | 4% | — |
| LiveBench Math | — | 41.6% |
| LMArena Math | 1408 | — |
Knowledge Not comparable
Grok 4.1 Fast: 33.1 (#207), Sonar: —
| Benchmark | Grok 4.1 Fast | Sonar |
|---|---|---|
| Vectara Hallucination Rate | 17.8% | — |
| LMArena Expert | 1399 | — |
Multimodal Not comparable
Grok 4.1 Fast: 37.0 (#76), Sonar: —
| Benchmark | Grok 4.1 Fast | Sonar |
|---|---|---|
| LMArena Vision | 1201 | — |
Multilingual Not comparable
Grok 4.1 Fast: 51.0 (#114), Sonar: —
| Benchmark | Grok 4.1 Fast | Sonar |
|---|---|---|
| LMArena Non-English | 1391 | — |
| LMArena Chinese | 1441 | — |
| LMArena French | 1415 | — |
| LMArena German | 1404 | — |
| LMArena Japanese | 1349 | — |
| LMArena Korean | 1361 | — |
| LMArena Russian | 1387 | — |
| LMArena Spanish | 1413 | — |
Instruction Following Grok 4.1 Fast leads
Grok 4.1 Fast: 72.7 (#133), Sonar: 71.4 (#150)
| Benchmark | Grok 4.1 Fast | Sonar |
|---|---|---|
| LiveBench Instruction Following | — | 76.2% |
| LMArena Instruction Following | 1376 | — |
Long Context Not comparable
Grok 4.1 Fast: 42.4 (#126), Sonar: —
| Benchmark | Grok 4.1 Fast | Sonar |
|---|---|---|
| LMArena Longer Query | 1390 | — |
Writing & Preference Grok 4.1 Fast leads
Grok 4.1 Fast: 57.2 (#131), Sonar: 52.6 (#167)
| Benchmark | Grok 4.1 Fast | Sonar |
|---|---|---|
| LMArena Text | 1408 | — |
| LMArena Creative Writing | 1394 | — |
| EQ-Bench Creative Writing | 1327 | — |
| LMArena Multi-Turn | 1389 | — |
| LiveBench Language | — | 44.1% |
Frequently asked questions
Is Grok 4.1 Fast better than Sonar?
Grok 4.1 Fast is the stronger model overall, scoring 41.4 to 38.5 on the Noometry Index.
Which is cheaper, Grok 4.1 Fast or Sonar?
Grok 4.1 Fast is cheaper. It lists at $0.20 per million input tokens and $0.50 per million output tokens; Sonar lists at $1 and $1.
Is Grok 4.1 Fast or Sonar better for coding?
Sonar scores higher on coding benchmarks: 35.7 versus 34.1 in the Noometry coding category.
Which has the bigger context window?
Both accept 128K tokens.
How many benchmarks do Grok 4.1 Fast and Sonar share?
0 benchmarks have published results for both models. Grok 4.1 Fast has 32 scored results on Noometry and Sonar has 7.