# GPT-5.3 Codex vs Grok Build 0.1

> GPT-5.3 Codex is the stronger model overall, scoring 45.5 to 35.8 on the Noometry Index. Grok Build 0.1 costs 3.9× less per token, which makes it the better buy when GPT-5.3 Codex's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/gpt-5-3-codex-vs-grok-build-0-1
- Last updated: 2026-10-10
- Shared benchmarks: 0

## Summary

- The widest gap is in agentic & tool use, where GPT-5.3 Codex leads 47.8 to 22.5.
- Grok Build 0.1 is cheaper at $1 / $2 per million input/output tokens, against $1.75 / $14 for GPT-5.3 Codex.
- GPT-5.3 Codex accepts more context: 400K tokens versus 256K.

## Snapshot

| | GPT-5.3 Codex | Grok Build 0.1 |
|---|---|---|
| Provider | OpenAI | xAI |
| Noometry Index | 45.5 | 35.8 |
| Rank | 61 | 214 |
| Context | 400K | 256K |
| Input $/M | $1.75 | $1 |
| Output $/M | $14 | $2 |
| Weights | Proprietary | Proprietary |

## Coding

- GPT-5.3 Codex: 48.5 (#51)
- Grok Build 0.1: 42.5 (#90)

| Benchmark | GPT-5.3 Codex | Grok Build 0.1 |
|---|---|---|
| SWE-bench Verified | 74.8% | — |
| LMArena WebDev | 1408 | — |
| SciCode | — | 50.2% |
| WeirdML | 79.3% | — |
| ALE-Bench | 1,655 | — |

## Agentic & Tool Use

- GPT-5.3 Codex: 47.8 (#9)
- Grok Build 0.1: 22.5 (#122)

| Benchmark | GPT-5.3 Codex | Grok Build 0.1 |
|---|---|---|
| Terminal-Bench | 78.4% | — |
| GBAEval | — | 2.4% |
| METR Time Horizons | 74.5% | — |
| Vending-Bench 2 | 5,940 | — |

## Reasoning

- GPT-5.3 Codex: —
- Grok Build 0.1: 31.3 (#73)

| Benchmark | GPT-5.3 Codex | Grok Build 0.1 |
|---|---|---|
| CritPt | — | 9.1% |
| Epoch Capabilities Index | 156.84 | — |

## FAQ

### Is GPT-5.3 Codex better than Grok Build 0.1?

GPT-5.3 Codex is the stronger model overall, scoring 45.5 to 35.8 on the Noometry Index. Grok Build 0.1 costs 3.9× less per token, which makes it the better buy when GPT-5.3 Codex's lead doesn't matter for your workload.

### Which is cheaper, GPT-5.3 Codex or Grok Build 0.1?

Grok Build 0.1 is cheaper. It lists at $1 per million input tokens and $2 per million output tokens; GPT-5.3 Codex lists at $1.75 and $14.

### Is GPT-5.3 Codex or Grok Build 0.1 better for coding?

GPT-5.3 Codex scores higher on coding benchmarks: 48.5 versus 42.5 in the Noometry coding category.

### Which has the bigger context window?

GPT-5.3 Codex does, with 400K tokens against 256K.

### How many benchmarks do GPT-5.3 Codex and Grok Build 0.1 share?

0 benchmarks have published results for both models. GPT-5.3 Codex has 8 scored results on Noometry and Grok Build 0.1 has 3.