# GPT-5.3 Codex vs Muse Spark 1.3

> Side-by-side benchmark comparison for GPT-5.3 Codex and Muse Spark 1.3 across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/gpt-5-3-codex-vs-muse-spark-1-3
- Last updated: October 17, 2026

- Shared sourced benchmarks: 1
- HTML indexing: indexable
- Ranking lane: BenchAlign v5.8

## Quick Verdict

Evidence is too thin for a benchmark verdict: GPT-5.3 Codex and Muse Spark 1.3 share only 1 sourced benchmark row.

## Summary

- Only 1 shared sourced benchmark row is available. That is not enough for a broad capability verdict, so this mirror does not name an overall winner.
- Muse Spark 1.3 has the lower published output-token price.
- Muse Spark 1.3 has the larger published context window at 1M.

## Model Snapshot

| Property | GPT-5.3 Codex | Muse Spark 1.3 |
|----------|----------|----------|
| Creator | OpenAI | Meta |
| Type | Proprietary | Proprietary |
| Reasoning | Reasoning | Reasoning |
| Context | 400K | 1M |
| Independent public score (not head-to-head) | 60.48 | null |
| Benchmarks Covered | 11 | 20 |
| Pricing (input/output) | $1.75 / $14.00 | $1.25 / $4.25 |

## Category Breakdown

### Agentic

- Winner: Insufficient shared evidence
- GPT-5.3 Codex public-lane score: 55.5 (Estimated · #41/128)
- Muse Spark 1.3 public-lane score: Coming soon

| Benchmark | GPT-5.3 Codex | Muse Spark 1.3 | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 2.0 | 77.3% | Coming soon | Coming soon |
| OSWorld-Verified | 64.7% | Coming soon | Coming soon |
| Gert Labs | 57.47% | Coming soon | Coming soon |
| JobBench | 33.7% | 64.9% | Muse Spark 1.3 |
| Terminal-Bench 2.1 | Coming soon | 88.8% | Coming soon |
| OSWorld 2.0 | Coming soon | 66.9% | Coming soon |
| DeepSearchQA | Coming soon | 89.4% | Coming soon |
| AutomationBench | Coming soon | 49.4% | Coming soon |
| ApprenticeBench | Coming soon | 19% | Coming soon |
| Terminal-Bench 2.1 (Vals) | Coming soon | 72.3% | Coming soon |
| CWE-bench v1 | Coming soon | 55.0% | Coming soon |
| MazeBench | Coming soon | 0% | Coming soon |

### Coding

- Winner: Insufficient shared evidence
- GPT-5.3 Codex public-lane score: 53.5 (Supported · #35/150)
- Muse Spark 1.3 public-lane score: Coming soon

| Benchmark | GPT-5.3 Codex | Muse Spark 1.3 | Winner |
|-----------|-----------|-----------|--------|
| SWE-bench Verified | 85% | Coming soon | Coming soon |
| SWE-bench Pro | 56.8% | Coming soon | Coming soon |
| SWE-Rebench | 58.2% | Coming soon | Coming soon |
| Terminal-Bench 2.0 | 77.3% | Coming soon | Coming soon |
| Vibe Code Bench | 61.77% | Coming soon | Coming soon |
| LiveCodeBench (Vals) | 87.3% | Coming soon | Coming soon |
| SWE-bench (Vals) | 78.0% | Coming soon | Coming soon |
| Terminal-Bench 2.1 | Coming soon | 88.8% | Coming soon |
| DeepSWE | Coming soon | 75.4% | Coming soon |
| SWE-Atlas Codebase QnA | Coming soon | 59.4% | Coming soon |
| CursorBench 4.0 | Coming soon | 41.6% | Coming soon |
| Bug Hunt Bench | Coming soon | 32.2 fixes | Coming soon |
| FrontierSWE v2 | Coming soon | 25.8% | Coming soon |

### Reasoning

- Winner: Insufficient shared evidence
- GPT-5.3 Codex public-lane score: 83.1 (Unranked · 2 rankable rows)
- Muse Spark 1.3 public-lane score: 82.9 (#6/28)

| Benchmark | GPT-5.3 Codex | Muse Spark 1.3 | Winner |
|-----------|-----------|-----------|--------|
| MRCR v2 256K-512K | Coming soon | 98.5% | Coming soon |
| MRCR v2 512K-1M | Coming soon | 98.1% | Coming soon |

### Multimodal & Grounded

- Winner: Insufficient shared evidence
- GPT-5.3 Codex public-lane score: 80.1 (Unranked · 1 rankable row)
- Muse Spark 1.3 public-lane score: Coming soon

### Knowledge

- Winner: Insufficient shared evidence
- GPT-5.3 Codex public-lane score: 65.4 (Estimated · #33/184)
- Muse Spark 1.3 public-lane score: Coming soon

### Instruction Following

- Winner: Insufficient shared evidence
- GPT-5.3 Codex public-lane score: 92.6 (#18/148)
- Muse Spark 1.3 public-lane score: Coming soon

| Benchmark | GPT-5.3 Codex | Muse Spark 1.3 | Winner |
|-----------|-----------|-----------|--------|
| Gray Swan IPI (15 attempts) | Coming soon | 15.9% | Coming soon |

### Mathematics

- Winner: Insufficient shared evidence
- GPT-5.3 Codex public-lane score: Coming soon
- Muse Spark 1.3 public-lane score: 78.5 (Unranked · 2 rankable rows)

| Benchmark | GPT-5.3 Codex | Muse Spark 1.3 | Winner |
|-----------|-----------|-----------|--------|
| FrontierMath v2 (Tiers 1-3) | Coming soon | 74.035% | Coming soon |
| FrontierMath v2 (Tier 4) | Coming soon | 46.341% | Coming soon |

## FAQ

### Is there enough evidence to pick between GPT-5.3 Codex and Muse Spark 1.3?

Not yet. The models share only 1 sourced benchmark row, so this mirror reports the available measurements and metadata without naming a broad winner.

### What can I compare safely on this page?

Published pricing, context windows, model type, and individual shared benchmark rows are directly comparable. Independent overall scores and non-overlapping benchmark coverage are labeled separately and should not be read as a controlled head-to-head result.

## Related Comparisons

- [GPT-5.3 Codex vs GPT-5.3-Codex-Spark](/compare/gpt-5-3-codex-vs-gpt-5-3-codex-spark)
- [Muse Spark 1.3 vs GPT-5.3-Codex-Spark](/compare/gpt-5-3-codex-spark-vs-muse-spark-1-3)
- [GPT-5.3 Codex vs Muse Spark 1.1](/compare/gpt-5-3-codex-vs-muse-spark-1-1)
- [Muse Spark 1.3 vs Muse Spark 1.1](/compare/muse-spark-1-1-vs-muse-spark-1-3)

## Explore More

- [GPT-5.3 Codex profile](/models/gpt-5-3-codex)
- [Muse Spark 1.3 profile](/models/muse-spark-1-3)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)