picksbymodel Get API access →
head-to-head

OpenAI: GPT-5.3-Codex vs Google: Gemini 3.1 Pro Preview

Side-by-side comparison of specs, pricing, benchmark scores, and task rankings. Updated 2026-09-23.

OpenAI: GPT-5.3-Codex Google: Gemini 3.1 Pro Preview
Vendoropenaigoogle
Quality Score100100
Benchmark Score53.366.5
Input Price$1.75/M$2.00/M
Output Price$14.00/M$12.00/M
Context Window400,0001,048,576
Max Output128,00065,536
Tool Calling✓✓
Structured Output✓✓
Reasoning Mode✓✓
Vision✓✓
Audio-✓
Benchmark Scores
ai_index53.649.0
eqbench-74.3

Who wins by task?

TaskOpenAI: GPT-5.3-CodexGoogle: Gemini 3.1 Pro Preview
SQL Generation 138 143
Code Review 142 150
Code Completion 117 120
Code Refactoring 144 153
Bug Fixing 146 154
Unit Test Generation 130 135
Code Documentation 133 139
Regex Writing 122 125
CI/CD Pipelines 126 131
Frontend Component Design 128 130
Data Analysis 132 135
CSV / Spreadsheet Cleanup 134 139
ETL Scripting 135 142
JSON Extraction 120 121
Bulk Data Labeling 117 117
OCR / Document Parsing 133 135
Table Extraction from PDFs 133 135
Long-Document Summarization 145 154
Short-Form Summarization 115 117
Blog Post Writing 126 131

Scores reflect capability match + benchmark data + pricing for each task. Methodology →

Related comparisons

Anthropic: Claude Haiku Latest vs Google: Gemini 3.1 Pro Preview Anthropic: Claude Haiku Latest vs OpenAI: GPT-5.3-Codex Anthropic: Claude Sonnet Latest vs Google: Gemini 3.1 Pro Preview Anthropic: Claude Sonnet Latest vs OpenAI: GPT-5.3-Codex ByteDance Seed: Seed-2.0-Lite vs Google: Gemini 3.1 Pro Preview ByteDance Seed: Seed-2.0-Lite vs OpenAI: GPT-5.3-Codex ByteDance Seed: Seed-2.0-Mini vs Google: Gemini 3.1 Pro Preview ByteDance Seed: Seed-2.0-Mini vs OpenAI: GPT-5.3-Codex

The Model Movers Report

One email every Friday, built from this site's own rankings: the current top five by benchmark score, every model released in the last seven days, and one note worked out from that week's numbers. You can unsubscribe from any issue with one click.