head-to-head

SpaceXAI: Grok 4.6 vs OpenAI: GPT-5.6 Sol Pro

Side-by-side comparison of specs, pricing, benchmark scores, and task rankings. Updated 2026-10-02.

SpaceXAI: Grok 4.6 OpenAI: GPT-5.6 Sol Pro
Vendorx-aiopenai
Quality Score10098
Benchmark Score75.3-
Input Price$2.00/M$4.00/M
Output Price$6.00/M$20.00/M
Context Window500,0001,050,000
Max Output450,000128,000
Tool Calling✓✓
Structured Output✓✓
Reasoning Mode✓✓
Vision✓✓
Audio--
Benchmark Scores
ai_index73.1-

The verdict

For a sample job of 1 million input tokens and 250,000 output tokens, Grok 4.6 costs $3.50 and GPT-5.6 Sol Pro costs $9.00, so Grok 4.6 is about 2.6 times cheaper for the same work.

GPT-5.6 Sol Pro reads up to 1,050,000 tokens at once, roughly 1,575 pages of text, against about 750 pages for Grok 4.6.

Across the 20 tasks where they differ, Grok 4.6 scores higher on 20 (SQL Generation, Code Review, Code Completion and others).

Grok 4.6 was released in August 2026 and GPT-5.6 Sol Pro in July 2026.

Pick Grok 4.6 if you need lower cost or the stronger all-round task scores; pick GPT-5.6 Sol Pro if you need long documents.

Costs use current list prices per million tokens; page counts assume about 0.75 words per token and 500 words per page.

Who wins by task?

TaskSpaceXAI: Grok 4.6OpenAI: GPT-5.6 Sol Pro
SQL Generation 142 129
Code Review 145 130
Code Completion 119 113
Code Refactoring 147 134
Bug Fixing 149 134
Unit Test Generation 132 122
Code Documentation 137 125
Regex Writing 125 113
CI/CD Pipelines 128 118
Frontend Component Design 130 120
Data Analysis 135 122
CSV / Spreadsheet Cleanup 136 129
ETL Scripting 138 126
JSON Extraction 122 117
Bulk Data Labeling 119 112
OCR / Document Parsing 134 129
Table Extraction from PDFs 134 129
Long-Document Summarization 148 133
Short-Form Summarization 118 109
Blog Post Writing 130 117

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

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