head-to-head

Google: Gemma 4 31B (free) vs Google: Gemini 3.1 Pro Preview Custom Tools

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

	Google: Gemma 4 31B (free)	Google: Gemini 3.1 Pro Preview Custom Tools
Vendor	google	google
Quality Score	100	100
Benchmark Score	53.7	-
Input Price	Free	$2.00/M
Output Price	Free	$12.00/M
Context Window	262,144	1,048,576
Max Output	32,768	65,536
Tool Calling	✓	✓
Structured Output	✓	✓
Reasoning Mode	✓	✓
Vision	✓	✓
Audio	-	✓
Benchmark Scores
ai_index	31.3	-
eqbench	70.8	-

Who wins by task?

Task	Google: Gemma 4 31B (free)	Google: Gemini 3.1 Pro Preview Custom Tools
SQL Generation	140	132
Code Review	140	132
Code Completion	132	117
Code Refactoring	141	136
Bug Fixing	144	136
Unit Test Generation	130	124
Code Documentation	135	129
Regex Writing	126	117
CI/CD Pipelines	126	120
Frontend Component Design	128	122
Data Analysis	132	124
CSV / Spreadsheet Cleanup	134	132
ETL Scripting	133	128
JSON Extraction	132	121
Bulk Data Labeling	130	117
OCR / Document Parsing	131	131
Table Extraction from PDFs	131	131
Long-Document Summarization	143	136
Short-Form Summarization	127	113
Blog Post Writing	128	120

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