OpenAI: GPT-5.6 Sol Pro (batch) vs SpaceXAI: Grok 4.5

For a sample job of 1 million input tokens and 250,000 output tokens, Grok 4.5 costs $3.50 and GPT-5.6 Sol Pro (batch) costs $4.50, so Grok 4.5 is about 1.3 times cheaper for the same work.

GPT-5.6 Sol Pro (batch) reads up to 1,050,000 tokens at once, roughly 1,575 pages of text, against about 750 pages for Grok 4.5.

Across the 20 tasks where they differ, Grok 4.5 on 20 (SQL Generation, Code Review, Code Completion and others).

Pick GPT-5.6 Sol Pro (batch) if you need long documents; pick Grok 4.5 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.