# GPT-5.3 Codex vs Qwen3.8-27B

> Side-by-side benchmark comparison for GPT-5.3 Codex and Qwen3.8-27B across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/gpt-5-3-codex-vs-qwen3-8-27b
- Last updated: September 28, 2026

- Shared sourced benchmarks: 5
- HTML indexing: indexable
- Ranking lane: BenchAlign v5.7

## Quick Verdict

Pick GPT-5.3 Codex if you want the stronger benchmark profile. Qwen3.8-27B only makes more sense when its price, context window, or workload-specific category wins matter more than the overall score.

## Summary

- GPT-5.3 Codex leads overall 62.06 to 55.26.
- The clearest category separation is in knowledge, where the averages are 64.2 for GPT-5.3 Codex and 49.2 for Qwen3.8-27B.
- The biggest single benchmark swing is OSWorld-Verified in Agentic, with scores of 64.7% and 84.3%.
- Qwen3.8-27B is the cheaper option on output tokens, which matters if you expect large responses or heavy interactive use.
- GPT-5.3 Codex also has the larger context window at 400K.

## Model Snapshot

| Property | GPT-5.3 Codex | Qwen3.8-27B |
|----------|----------|----------|
| Creator | OpenAI | Alibaba |
| Type | Proprietary | Open Weight |
| Reasoning | Reasoning | Reasoning |
| Context | 400K | 262K |
| Overall Score | 62.06 | 55.26 |
| Benchmarks Covered | 10 | 33 |
| Pricing (input/output) | $1.75 / $14.00 | $0.00 / $0.00 |

## Category Breakdown

### Agentic

- Winner: Directional only
- GPT-5.3 Codex public-lane score: 54.2 (Estimated · #35/117)
- Qwen3.8-27B public-lane score: 61.2 (Supported · #18/117)

| Benchmark | GPT-5.3 Codex | Qwen3.8-27B | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 2.0 | 77.3% | Coming soon | Coming soon |
| OSWorld-Verified | 64.7% | 84.3% | Qwen3.8-27B |
| Gert Labs | 57.47% | Coming soon | Coming soon |
| JobBench | 33.7% | 33.4% | GPT-5.3 Codex |
| Terminal-Bench 2.1 | Coming soon | 73.0% | Coming soon |
| CoWorkBench | Coming soon | 70.7% | Coming soon |
| Agents' Last Exam | Coming soon | 42.9% | Coming soon |
| WebArena-Verified | Coming soon | 64.8% | Coming soon |
| AndroidWorld | Coming soon | 81.9% | Coming soon |
| Terminal-Bench 2.1 (Vals) | Coming soon | 58.4% | Coming soon |

### Coding

- Winner: GPT-5.3 Codex
- GPT-5.3 Codex public-lane score: 55.4 (Supported · #28/142)
- Qwen3.8-27B public-lane score: 48.7 (Supported · #45/142)

| Benchmark | GPT-5.3 Codex | Qwen3.8-27B | Winner |
|-----------|-----------|-----------|--------|
| SWE-bench Verified | 85% | Coming soon | Coming soon |
| SWE-bench Pro | 56.8% | 61.7% | Qwen3.8-27B |
| SWE-Rebench | 58.2% | Coming soon | Coming soon |
| Vibe Code Bench | 61.77% | Coming soon | Coming soon |
| LiveCodeBench (Vals) | 87.3% | 84.0% | GPT-5.3 Codex |
| SWE-bench (Vals) | 78.0% | 86.0% | Qwen3.8-27B |
| Terminal-Bench 2.1 | Coming soon | 73.0% | Coming soon |
| NL2Repo | Coming soon | 42.3% | Coming soon |
| DeepSWE | Coming soon | 42.2% | Coming soon |
| LiveCodeBench v6 | Coming soon | 90.3% | Coming soon |
| VulcanBench v3 | Coming soon | 82.6% | Coming soon |

### Reasoning

- Winner: Not comparable
- GPT-5.3 Codex public-lane score: 79.6 (Unranked · 2 rankable rows)
- Qwen3.8-27B public-lane score: 78.7 (#8/27)

### Multimodal & Grounded

- Winner: Not comparable
- GPT-5.3 Codex public-lane score: 76.7 (Unranked · 1 rankable row)
- Qwen3.8-27B public-lane score: 80.9 (#11/50)

| Benchmark | GPT-5.3 Codex | Qwen3.8-27B | Winner |
|-----------|-----------|-----------|--------|
| MathVision | Coming soon | 90.0% | Coming soon |
| MathVision w/ Python | Coming soon | 94.6% | Coming soon |
| BabyVision | Coming soon | 65.7% | Coming soon |
| BabyVision w/ Python | Coming soon | 85.6% | Coming soon |
| Vision2Web | Coming soon | 62.9% | Coming soon |
| CharXiv w/o tools | Coming soon | 83.7% | Coming soon |
| CharXiv | Coming soon | 90.2% | Coming soon |
| OmniDocBench 1.5 | Coming soon | 91.1% | Coming soon |
| RealWorldQA | Coming soon | 85.9% | Coming soon |
| ERQA | Coming soon | 65.5% | Coming soon |

### Knowledge

- Winner: Directional only
- GPT-5.3 Codex public-lane score: 64.2 (Estimated · #29/168)
- Qwen3.8-27B public-lane score: 49.2 (Supported · #63/168)

| Benchmark | GPT-5.3 Codex | Qwen3.8-27B | Winner |
|-----------|-----------|-----------|--------|
| GPQA | Coming soon | 89.2% | Coming soon |
| GPQA-D | Coming soon | 89.2% | Coming soon |
| HLE | Coming soon | 30.8% | Coming soon |
| HLE w/o tools | Coming soon | 30.8% | Coming soon |
| GPQA Diamond (Vals) | Coming soon | 88.9% | Coming soon |
| MMLU-Pro (Vals) | Coming soon | 84.3% | Coming soon |

### Instruction Following

- Winner: Directional only
- GPT-5.3 Codex public-lane score: 91.2 (#14/124)
- Qwen3.8-27B public-lane score: 83.2 (#45/124)

| Benchmark | GPT-5.3 Codex | Qwen3.8-27B | Winner |
|-----------|-----------|-----------|--------|
| IFBench | Coming soon | 79.5% | Coming soon |

## FAQ

### Which is better overall, GPT-5.3 Codex or Qwen3.8-27B?

GPT-5.3 Codex is ahead overall on BenchLM right now.

### Where is the biggest gap between GPT-5.3 Codex and Qwen3.8-27B?

The widest category gap is in knowledge, where the averages are 64.2 for GPT-5.3 Codex and 49.2 for Qwen3.8-27B.

### How many benchmarks does GPT-5.3 Codex cover on BenchLM?

GPT-5.3 Codex currently has 10 sourced benchmark scores on BenchLM.

### How many benchmarks does Qwen3.8-27B cover on BenchLM?

Qwen3.8-27B currently has 33 sourced benchmark scores on BenchLM.

## Related Comparisons

- [GPT-5.3 Codex vs GPT-5.3-Codex-Spark](/compare/gpt-5-3-codex-vs-gpt-5-3-codex-spark)
- [Qwen3.8-27B vs GPT-5.3-Codex-Spark](/compare/gpt-5-3-codex-spark-vs-qwen3-8-27b)
- [GPT-5.3 Codex vs GPT-6 Astra](/compare/gpt-5-3-codex-vs-gpt-6-astra)
- [Qwen3.8-27B vs GPT-6 Astra](/compare/gpt-6-astra-vs-qwen3-8-27b)

## Explore More

- [GPT-5.3 Codex profile](/models/gpt-5-3-codex)
- [Qwen3.8-27B profile](/models/qwen3-8-27b)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)