head-to-head

SpaceXAI: Grok 4.3 vs OpenAI: GPT-5.3-Codex

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

SpaceXAI: Grok 4.3 OpenAI: GPT-5.3-Codex
Vendorx-aiopenai
Quality Score100100
Benchmark Score39.353.3
Input Price$1.25/M$1.75/M
Output Price$2.50/M$14.00/M
Context Window1,000,000400,000
Max Output900,000128,000
Tool Calling
Structured Output
Reasoning Mode
Vision
Audio--
Benchmark Scores
ai_index41.153.6

Who wins by task?

TaskSpaceXAI: Grok 4.3OpenAI: GPT-5.3-Codex
SQL Generation 138 138
Code Review 139 142
Code Completion 120 117
Code Refactoring 142 144
Bug Fixing 143 146
Unit Test Generation 128 130
Code Documentation 134 133
Regex Writing 123 122
CI/CD Pipelines 124 126
Frontend Component Design 126 128
Data Analysis 130 132
CSV / Spreadsheet Cleanup 135 134
ETL Scripting 133 135
JSON Extraction 123 120
Bulk Data Labeling 120 117
OCR / Document Parsing 133 133
Table Extraction from PDFs 133 133
Long-Document Summarization 144 145
Short-Form Summarization 117 115
Blog Post Writing 126 126

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

Related comparisons

Anthropic: Claude Haiku Latest vs OpenAI: GPT-5.3-Codex Anthropic: Claude Opus 5 (batch) vs SpaceXAI: Grok 4.3 Anthropic: Claude Sonnet 5 (batch) vs SpaceXAI: Grok 4.3 Anthropic: Claude Sonnet 5 vs SpaceXAI: Grok 4.3 Anthropic: Claude Sonnet Latest vs OpenAI: GPT-5.3-Codex ByteDance Seed: Seed-2.0-Lite vs OpenAI: GPT-5.3-Codex ByteDance Seed: Seed-2.0-Mini vs OpenAI: GPT-5.3-Codex Google: Gemini 3.1 Flash Lite Preview 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.