# GPT-5-Codex vs Llama 3.1 Nemotron 51b Instruct

> GPT-5-Codex is the stronger model overall, scoring 37.9 to 35.9 on the Noometry Index.

- Canonical page: https://noometry.com/compare/gpt-5-codex-vs-llama-3-1-nemotron-51b-instruct
- Last updated: 2026-10-12
- Shared benchmarks: 0

## Summary

- The widest gap is in reasoning, where GPT-5-Codex leads 30.9 to 23.5.
- Llama 3.1 Nemotron 51b Instruct has downloadable open weights; the other is API-only.

## Snapshot

| | GPT-5-Codex | Llama 3.1 Nemotron 51b Instruct |
|---|---|---|
| Provider | OpenAI | NVIDIA |
| Noometry Index | 37.9 | 35.9 |
| Rank | 192 | 222 |
| Context | 400K | — |
| Input $/M | $1.25 | — |
| Output $/M | $10 | — |
| Weights | Proprietary | Open |

## Coding

- GPT-5-Codex: 42.4 (#103)
- Llama 3.1 Nemotron 51b Instruct: 35.6 (#222)

| Benchmark | GPT-5-Codex | Llama 3.1 Nemotron 51b Instruct |
|---|---|---|
| WeirdML | 54.5% | — |
| LMArena Coding | — | 1223 |

## Agentic & Tool Use

- GPT-5-Codex: 31.0 (#72)
- Llama 3.1 Nemotron 51b Instruct: —

| Benchmark | GPT-5-Codex | Llama 3.1 Nemotron 51b Instruct |
|---|---|---|
| Terminal-Bench | 44.3% | — |

## Reasoning

- GPT-5-Codex: 30.9 (#83)
- Llama 3.1 Nemotron 51b Instruct: 23.5 (#177)

| Benchmark | GPT-5-Codex | Llama 3.1 Nemotron 51b Instruct |
|---|---|---|
| Kagi LLM Benchmark | 70.3% | — |
| LMArena Hard Prompts | — | 1203 |

## Math

- GPT-5-Codex: —
- Llama 3.1 Nemotron 51b Instruct: 34.6 (#193)

| Benchmark | GPT-5-Codex | Llama 3.1 Nemotron 51b Instruct |
|---|---|---|
| LMArena Math | — | 1230 |

## Knowledge

- GPT-5-Codex: —
- Llama 3.1 Nemotron 51b Instruct: 31.9 (#218)

| Benchmark | GPT-5-Codex | Llama 3.1 Nemotron 51b Instruct |
|---|---|---|
| LMArena Expert | — | 1167 |

## Multilingual

- GPT-5-Codex: —
- Llama 3.1 Nemotron 51b Instruct: 36.1 (#241)

| Benchmark | GPT-5-Codex | Llama 3.1 Nemotron 51b Instruct |
|---|---|---|
| LMArena Non-English | — | 1181 |
| LMArena Chinese | — | 1180 |
| LMArena Russian | — | 1187 |

## Instruction Following

- GPT-5-Codex: —
- Llama 3.1 Nemotron 51b Instruct: 62.9 (#233)

| Benchmark | GPT-5-Codex | Llama 3.1 Nemotron 51b Instruct |
|---|---|---|
| LMArena Instruction Following | — | 1201 |

## Long Context

- GPT-5-Codex: —
- Llama 3.1 Nemotron 51b Instruct: 36.5 (#230)

| Benchmark | GPT-5-Codex | Llama 3.1 Nemotron 51b Instruct |
|---|---|---|
| LMArena Longer Query | — | 1205 |

## Writing & Preference

- GPT-5-Codex: —
- Llama 3.1 Nemotron 51b Instruct: 43.4 (#229)

| Benchmark | GPT-5-Codex | Llama 3.1 Nemotron 51b Instruct |
|---|---|---|
| LMArena Text | — | 1228 |
| LMArena Creative Writing | — | 1213 |
| LMArena Multi-Turn | — | 1227 |

## FAQ

### Is GPT-5-Codex better than Llama 3.1 Nemotron 51b Instruct?

GPT-5-Codex is the stronger model overall, scoring 37.9 to 35.9 on the Noometry Index.

### Is GPT-5-Codex or Llama 3.1 Nemotron 51b Instruct better for coding?

GPT-5-Codex scores higher on coding benchmarks: 42.4 versus 35.6 in the Noometry coding category.

### How many benchmarks do GPT-5-Codex and Llama 3.1 Nemotron 51b Instruct share?

0 benchmarks have published results for both models. GPT-5-Codex has 3 scored results on Noometry and Llama 3.1 Nemotron 51b Instruct has 12.