# GPT-5.3 Codex vs Qwen3.5 Plus

> GPT-5.3 Codex is the stronger model overall, scoring 45.8 to 42.9 on the Noometry Index. Qwen3.5 Plus costs 5.3× 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-qwen3-5-plus
- Last updated: 2026-10-11
- Shared benchmarks: 3

## Summary

- They share 3 benchmarks with published results for both.
- Qwen3.5 Plus is cheaper at $0.40 / $2.40 per million input/output tokens, against $1.75 / $14 for GPT-5.3 Codex.
- Qwen3.5 Plus accepts more context: 1M tokens versus 400K.

## Snapshot

| | GPT-5.3 Codex | Qwen3.5 Plus |
|---|---|---|
| Provider | OpenAI | Alibaba (Qwen) |
| Noometry Index | 45.8 | 42.9 |
| Rank | 69 | 106 |
| Context | 400K | 1M |
| Input $/M | $1.75 | $0.40 |
| Output $/M | $14 | $2.40 |
| Weights | Proprietary | Proprietary |

## Coding

- GPT-5.3 Codex: 48.6 (#56)
- Qwen3.5 Plus: —

| Benchmark | GPT-5.3 Codex | Qwen3.5 Plus |
|---|---|---|
| ALE-Bench | 1,655 | 621.92 |
| SWE-bench Verified | 74.8% | — |
| LMArena WebDev | 1409 | — |
| WeirdML | 79.3% | — |

## Agentic & Tool Use

- GPT-5.3 Codex: 48.0 (#9)
- Qwen3.5 Plus: —

| Benchmark | GPT-5.3 Codex | Qwen3.5 Plus |
|---|---|---|
| Vending-Bench 2 | 5,940 | 0.54 |
| Terminal-Bench | 78.4% | — |
| METR Time Horizons | 74.5% | — |

## Reasoning

- GPT-5.3 Codex: —
- Qwen3.5 Plus: 32.8 (#74)

| Benchmark | GPT-5.3 Codex | Qwen3.5 Plus |
|---|---|---|
| Epoch Capabilities Index | 156.77 | 146.78 |
| Chess Puzzles | — | 22% |
| Mystery Game Puzzles | — | 17% |
| DTBench | — | 80.5% |
| LMCA | — | 36.4% |

## Math

- GPT-5.3 Codex: —
- Qwen3.5 Plus: 49.6 (#61)

| Benchmark | GPT-5.3 Codex | Qwen3.5 Plus |
|---|---|---|
| OTIS Mock AIME 2024-2025 | — | 86.7% |
| FrontierMath (Feb 2025 set) | — | 21% |
| FrontierMath Tier 4 (v1) | — | 2.1% |

## Knowledge

- GPT-5.3 Codex: —
- Qwen3.5 Plus: 46.0 (#83)

| Benchmark | GPT-5.3 Codex | Qwen3.5 Plus |
|---|---|---|
| GPQA Diamond | — | 84.8% |
| SimpleQA Verified | — | 25.4% |
| Vectara Hallucination Rate | — | 10.7% |

## Long Context

- GPT-5.3 Codex: —
- Qwen3.5 Plus: 43.0 (#113)

| Benchmark | GPT-5.3 Codex | Qwen3.5 Plus |
|---|---|---|
| CL-bench | — | 19.8% |
| CL-bench Life | — | 12.4% |

## FAQ

### Is GPT-5.3 Codex better than Qwen3.5 Plus?

GPT-5.3 Codex is the stronger model overall, scoring 45.8 to 42.9 on the Noometry Index. Qwen3.5 Plus costs 5.3× 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 Qwen3.5 Plus?

Qwen3.5 Plus is cheaper. It lists at $0.40 per million input tokens and $2.40 per million output tokens; GPT-5.3 Codex lists at $1.75 and $14.

### Which has the bigger context window?

Qwen3.5 Plus does, with 1M tokens against 400K.

### How many benchmarks do GPT-5.3 Codex and Qwen3.5 Plus share?

3 benchmarks have published results for both models. GPT-5.3 Codex has 8 scored results on Noometry and Qwen3.5 Plus has 15.