# GPT-5.3 Chat vs Grok 4.20 Multi-Agent

> Grok 4.20 Multi-Agent is the stronger model overall, scoring 45.5 to 42.1 on the Noometry Index.

- Canonical page: https://noometry.com/compare/gpt-5-3-chat-vs-grok-4-20-multi-agent
- Last updated: 2026-10-10
- Shared benchmarks: 17

## Summary

- They share 17 benchmarks with published results for both. GPT-5.3 Chat scores higher in 0 categories and Grok 4.20 Multi-Agent in 8 categories; 7 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where Grok 4.20 Multi-Agent leads 42.4 to 27.3.
- Grok 4.20 Multi-Agent is cheaper at $1.25 / $2.50 per million input/output tokens, against $1.75 / $14 for GPT-5.3 Chat.
- Grok 4.20 Multi-Agent accepts more context: 1M tokens versus 128K.

## Snapshot

| | GPT-5.3 Chat | Grok 4.20 Multi-Agent |
|---|---|---|
| Provider | OpenAI | xAI |
| Noometry Index | 42.1 | 45.5 |
| Rank | 109 | 62 |
| Context | 128K | 1M |
| Input $/M | $1.75 | $1.25 |
| Output $/M | $14 | $2.50 |
| Weights | Proprietary | Proprietary |

## Coding

- GPT-5.3 Chat: 40.8 (#124)
- Grok 4.20 Multi-Agent: 42.4 (#91)

| Benchmark | GPT-5.3 Chat | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Coding | 1408 | 1458 |

## Agentic & Tool Use

- GPT-5.3 Chat: —
- Grok 4.20 Multi-Agent: —

| Benchmark | GPT-5.3 Chat | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Search | — | 1204 |

## Reasoning

- GPT-5.3 Chat: 27.3 (#105)
- Grok 4.20 Multi-Agent: 42.4 (#44)

| Benchmark | GPT-5.3 Chat | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Hard Prompts | 1399 | 1448 |
| NYT Connections (extended) | — | 89.6% |

## Math

- GPT-5.3 Chat: 35.4 (#146)
- Grok 4.20 Multi-Agent: 36.6 (#106)

| Benchmark | GPT-5.3 Chat | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Math | 1389 | 1441 |

## Knowledge

- GPT-5.3 Chat: 38.2 (#137)
- Grok 4.20 Multi-Agent: 39.7 (#116)

| Benchmark | GPT-5.3 Chat | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Expert | 1397 | 1445 |

## Multimodal

- GPT-5.3 Chat: —
- Grok 4.20 Multi-Agent: 39.8 (#44)

| Benchmark | GPT-5.3 Chat | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Vision | — | 1259 |

## Multilingual

- GPT-5.3 Chat: 50.5 (#119)
- Grok 4.20 Multi-Agent: 54.6 (#40)

| Benchmark | GPT-5.3 Chat | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Non-English | 1383 | 1440 |
| LMArena Chinese | 1433 | 1475 |
| LMArena French | 1398 | 1467 |
| LMArena German | 1384 | 1456 |
| LMArena Japanese | 1351 | 1405 |
| LMArena Korean | 1347 | 1416 |
| LMArena Russian | 1400 | 1457 |
| LMArena Spanish | 1371 | 1447 |

## Instruction Following

- GPT-5.3 Chat: 73.0 (#124)
- Grok 4.20 Multi-Agent: 75.0 (#80)

| Benchmark | GPT-5.3 Chat | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Instruction Following | 1378 | 1420 |

## Long Context

- GPT-5.3 Chat: 42.6 (#115)
- Grok 4.20 Multi-Agent: 43.7 (#84)

| Benchmark | GPT-5.3 Chat | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Longer Query | 1396 | 1430 |

## Writing & Preference

- GPT-5.3 Chat: 63.3 (#65)
- Grok 4.20 Multi-Agent: 64.1 (#57)

| Benchmark | GPT-5.3 Chat | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Text | 1389 | 1450 |
| LMArena Creative Writing | 1356 | 1435 |
| LMArena Multi-Turn | 1413 | 1451 |
| EQ-Bench Creative Writing | 1690 | — |

## FAQ

### Is GPT-5.3 Chat better than Grok 4.20 Multi-Agent?

Grok 4.20 Multi-Agent is the stronger model overall, scoring 45.5 to 42.1 on the Noometry Index.

### Which is cheaper, GPT-5.3 Chat or Grok 4.20 Multi-Agent?

Grok 4.20 Multi-Agent is cheaper. It lists at $1.25 per million input tokens and $2.50 per million output tokens; GPT-5.3 Chat lists at $1.75 and $14.

### Is GPT-5.3 Chat or Grok 4.20 Multi-Agent better for coding?

Grok 4.20 Multi-Agent scores higher on coding benchmarks: 42.4 versus 40.8 in the Noometry coding category.

### Which has the bigger context window?

Grok 4.20 Multi-Agent does, with 1M tokens against 128K.

### How many benchmarks do GPT-5.3 Chat and Grok 4.20 Multi-Agent share?

17 benchmarks have published results for both models. GPT-5.3 Chat has 18 scored results on Noometry and Grok 4.20 Multi-Agent has 20.