head-to-head

SpaceXAI: Grok 4.5 vs Google: Gemma 4 31B (free)

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

SpaceXAI: Grok 4.5 Google: Gemma 4 31B (free)
Vendorx-aigoogle
Quality Score100100
Benchmark Score91.253.7
Input Price$2.00/MFree
Output Price$6.00/MFree
Context Window500,000262,144
Max Output450,00032,768
Tool Calling✓✓
Structured Output✓✓
Reasoning Mode✓✓
Vision✓✓
Audio--
Benchmark Scores
ai_index88.848.4
ai_index_agentic75.423.8
ai_index_coding100.071.7
eqbench-57.5

The verdict

For a sample job of 1 million input tokens and 250,000 output tokens, Gemma 4 31B (free) costs $0 and Grok 4.5 costs $3.50, so Gemma 4 31B (free) is free for the same work.

Grok 4.5 reads up to 500,000 tokens at once, roughly 750 pages of text, against about 393 pages for Gemma 4 31B (free).

Only Gemma 4 31B (free) offers video input.

On our blended benchmark score Grok 4.5 leads 91.2 to 53.7.

Across the 20 tasks where they differ, Grok 4.5 scores higher on 16 (SQL Generation, Code Review, Code Refactoring and others), Gemma 4 31B (free) on 4 (Code Completion, JSON Extraction, Bulk Data Labeling and others).

Grok 4.5 was released in July 2026 and Gemma 4 31B (free) in April 2026.

Pick Grok 4.5 if you need long documents, benchmark performance or the stronger all-round task scores; pick Gemma 4 31B (free) if you need lower cost or video input.

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 4.5Google: Gemma 4 31B (free)
SQL Generation 171 156
Code Review 167 152
Code Completion 120 131
Code Refactoring 164 151
Bug Fixing 180 160
Unit Test Generation 154 143
Code Documentation 142 137
Regex Writing 135 131
CI/CD Pipelines 144 135
Frontend Component Design 146 138
Data Analysis 170 152
CSV / Spreadsheet Cleanup 154 145
ETL Scripting 154 143
JSON Extraction 139 143
Bulk Data Labeling 125 133
OCR / Document Parsing 146 140
Table Extraction from PDFs 146 140
Long-Document Summarization 159 149
Short-Form Summarization 123 129
Blog Post Writing 140 133

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

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