head-to-head

OpenAI: GPT-5.6 Terra Pro vs SpaceXAI: Grok 4.3

Side-by-side comparison of specs, pricing, benchmark scores, and task rankings. Updated 2026-11-07.

OpenAI: GPT-5.6 Terra Pro SpaceXAI: Grok 4.3
Vendoropenaix-ai
Quality Score100100
Benchmark Score-58.6
Input Price$2.00/M$1.25/M
Output Price$12.00/M$2.50/M
Context Window1,050,0001,000,000
Max Output128,000900,000
Tool Calling✓✓
Structured Output✓✓
Reasoning Mode✓✓
Vision✓✓
Audio--
Benchmark Scores
ai_index-62.0
ai_index_agentic-39.8
ai_index_coding-69.7

The verdict

For a sample job of 1 million input tokens and 250,000 output tokens, Grok 4.3 costs $1.88 and GPT-5.6 Terra Pro costs $5.00, so Grok 4.3 is about 2.7 times cheaper for the same work.

Both take in a similar amount of text: 1,050,000 and 1,000,000 tokens, about 1,575 and 1,500 pages.

Across the 20 tasks where they differ, Grok 4.3 on 20 (SQL Generation, Code Review, Code Completion and others).

GPT-5.6 Terra Pro was released in July 2026 and Grok 4.3 in April 2026.

Pick Grok 4.3 if you need lower cost or the stronger all-round task scores.

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?

TaskOpenAI: GPT-5.6 Terra ProSpaceXAI: Grok 4.3
SQL Generation 132 158
Code Review 132 155
Code Completion 117 120
Code Refactoring 136 155
Bug Fixing 136 164
Unit Test Generation 124 144
Code Documentation 129 139
Regex Writing 117 130
CI/CD Pipelines 120 136
Frontend Component Design 122 138
Data Analysis 124 153
CSV / Spreadsheet Cleanup 132 147
ETL Scripting 128 145
JSON Extraction 121 134
Bulk Data Labeling 117 124
OCR / Document Parsing 131 141
Table Extraction from PDFs 131 141
Long-Document Summarization 136 152
Short-Form Summarization 113 120
Blog Post Writing 120 134

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

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