# GPT-5.1 vs Sonar

> GPT-5.1 is the stronger model overall, scoring 49.0 to 38.5 on the Noometry Index. Sonar costs 3.4× less per token, which makes it the better buy when GPT-5.1's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/gpt-5-1-vs-sonar
- Last updated: 2026-10-11
- Shared benchmarks: 7

## Summary

- They share 7 benchmarks with published results for both. GPT-5.1 scores higher in 5 categories and Sonar in 0 categories; 5 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where GPT-5.1 leads 39.8 to 21.1.
- The biggest single-benchmark swing is LiveBench Math: 94.5% for GPT-5.1 and 41.6% for Sonar.
- Sonar is cheaper at $1 / $1 per million input/output tokens, against $1.25 / $10 for GPT-5.1.
- GPT-5.1 accepts more context: 400K tokens versus 128K.

## Snapshot

| | GPT-5.1 | Sonar |
|---|---|---|
| Provider | OpenAI | Perplexity |
| Noometry Index | 49.0 | 38.5 |
| Rank | 53 | 187 |
| Context | 400K | 128K |
| Input $/M | $1.25 | $1 |
| Output $/M | $10 | $1 |
| Weights | Proprietary | Proprietary |

## Coding

- GPT-5.1: 46.4 (#66)
- Sonar: 35.7 (#221)

| Benchmark | GPT-5.1 | Sonar |
|---|---|---|
| LiveBench Coding | 72.5% | 35.1% |
| SWE-bench Verified | 68% | — |
| SWE-bench Verified (bash only) | 66% | — |
| LMArena WebDev | 1395 | — |
| SciCode | 43.3% | — |
| GSO | 13.7% | — |
| WeirdML | 60.8% | — |
| LMArena Coding | 1454 | — |
| ALE-Bench | 1,192 | — |

## Agentic & Tool Use

- GPT-5.1: 32.7 (#60)
- Sonar: —

| Benchmark | GPT-5.1 | Sonar |
|---|---|---|
| Terminal-Bench | 47.6% | — |
| DeepResearch Bench | 42.8% | — |
| LMArena Search | 1199 | — |
| Vending-Bench 2 | 1,473 | — |

## Reasoning

- GPT-5.1: 39.8 (#58)
- Sonar: 21.1 (#227)

| Benchmark | GPT-5.1 | Sonar |
|---|---|---|
| LiveBench Reasoning | 95.8% | 46.3% |
| LiveBench Data Analysis | 72.1% | 37.9% |
| LiveBench | 78.8% | 46.9% |
| ARC-AGI-2 | 17.6% | — |
| SimpleBench | 53.2% | — |
| ARC-AGI-1 | 72.8% | — |
| CritPt | 4.9% | — |
| Chess Puzzles | 32% | — |
| EnigmaEval | 11.2% | — |
| LMArena Hard Prompts | 1457 | — |
| Mystery Game Puzzles | 19% | — |
| DTBench | 90.1% | — |
| LMCA | 43.9% | — |
| Epoch Capabilities Index | 149.64 | — |
| ForecastBench | 58.1 | — |

## Math

- GPT-5.1: 52.2 (#51)
- Sonar: 33.7 (#200)

| Benchmark | GPT-5.1 | Sonar |
|---|---|---|
| LiveBench Math | 94.5% | 41.6% |
| OTIS Mock AIME 2024-2025 | 88.6% | — |
| Omni-MATH | 46.4% | — |
| LMArena Math | 1447 | — |
| FrontierMath (Feb 2025 set) | 31% | — |
| FrontierMath Tier 4 (v1) | 12.5% | — |

## Knowledge

- GPT-5.1: 50.6 (#71)
- Sonar: —

| Benchmark | GPT-5.1 | Sonar |
|---|---|---|
| GPQA Diamond | 87.6% | — |
| Humanity's Last Exam | 23.7% | — |
| SimpleQA Verified | 48% | — |
| MMLU-Pro | 57.9% | — |
| Vectara Hallucination Rate | 10.9% | — |
| GPQA (HELM) | 44.2% | — |
| LMArena Expert | 1470 | — |

## Multimodal

- GPT-5.1: 44.8 (#19)
- Sonar: —

| Benchmark | GPT-5.1 | Sonar |
|---|---|---|
| LMArena Vision | 1250 | — |
| VPCT | 58.7% | — |
| LMArena Document | 1403 | — |

## Multilingual

- GPT-5.1: 53.8 (#56)
- Sonar: —

| Benchmark | GPT-5.1 | Sonar |
|---|---|---|
| LMArena Non-English | 1431 | — |
| LMArena Chinese | 1495 | — |
| LMArena French | 1450 | — |
| LMArena German | 1438 | — |
| LMArena Japanese | 1453 | — |
| LMArena Korean | 1401 | — |
| LMArena Russian | 1435 | — |
| LMArena Spanish | 1433 | — |

## Instruction Following

- GPT-5.1: 83.9 (#1)
- Sonar: 71.4 (#150)

| Benchmark | GPT-5.1 | Sonar |
|---|---|---|
| LiveBench Instruction Following | 93.3% | 76.2% |
| IFEval | 93.5% | — |
| LMArena Instruction Following | 1443 | — |

## Long Context

- GPT-5.1: 47.6 (#14)
- Sonar: —

| Benchmark | GPT-5.1 | Sonar |
|---|---|---|
| CL-bench | 23.7% | — |
| CL-bench Life | 17.3% | — |
| LMArena Longer Query | 1447 | — |

## Writing & Preference

- GPT-5.1: 64.5 (#55)
- Sonar: 52.6 (#167)

| Benchmark | GPT-5.1 | Sonar |
|---|---|---|
| LiveBench Language | 80.2% | 44.1% |
| LMArena Text | 1443 | — |
| LMArena Creative Writing | 1427 | — |
| WildBench | 86.3% | — |
| LMArena Multi-Turn | 1450 | — |

## FAQ

### Is GPT-5.1 better than Sonar?

GPT-5.1 is the stronger model overall, scoring 49.0 to 38.5 on the Noometry Index. Sonar costs 3.4× less per token, which makes it the better buy when GPT-5.1's lead doesn't matter for your workload.

### Which is cheaper, GPT-5.1 or Sonar?

Sonar is cheaper. It lists at $1 per million input tokens and $1 per million output tokens; GPT-5.1 lists at $1.25 and $10.

### Is GPT-5.1 or Sonar better for coding?

GPT-5.1 scores higher on coding benchmarks: 46.4 versus 35.7 in the Noometry coding category.

### Which has the bigger context window?

GPT-5.1 does, with 400K tokens against 128K.

### How many benchmarks do GPT-5.1 and Sonar share?

7 benchmarks have published results for both models. GPT-5.1 has 63 scored results on Noometry and Sonar has 7.