head-to-head

SpaceXAI: Grok 4.5 vs Google: Gemini 3.1 Flash Lite

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

SpaceXAI: Grok 4.5 Google: Gemini 3.1 Flash Lite
Vendorx-aigoogle
Quality Score100100
Benchmark Score91.2-
Input Price$2.00/M$0.25/M
Output Price$6.00/M$1.50/M
Context Window500,0001,048,576
Max Output450,00065,536
Tool Calling✓✓
Structured Output✓✓
Reasoning Mode✓✓
Vision✓✓
Audio-✓
Benchmark Scores
ai_index88.8-
ai_index_agentic75.4-
ai_index_coding100.0-

The verdict

For a sample job of 1 million input tokens and 250,000 output tokens, Gemini 3.1 Flash Lite costs $0.62 and Grok 4.5 costs $3.50, so Gemini 3.1 Flash Lite is about 5.6 times cheaper for the same work.

Gemini 3.1 Flash Lite reads up to 1,048,576 tokens at once, roughly 1,573 pages of text, against about 750 pages for Grok 4.5.

Only Gemini 3.1 Flash Lite offers audio input and video input.

Across the 20 tasks where they differ, Grok 4.5 scores higher on 17 (SQL Generation, Code Review, Code Refactoring and others), Gemini 3.1 Flash Lite on 3 (Code Completion, Bulk Data Labeling, Short-Form Summarization).

Grok 4.5 was released in July 2026 and Gemini 3.1 Flash Lite in May 2026.

Pick Grok 4.5 if you need the stronger all-round task scores; pick Gemini 3.1 Flash Lite if you need lower cost, long documents, audio input 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: Gemini 3.1 Flash Lite
SQL Generation 171 133
Code Review 167 132
Code Completion 120 131
Code Refactoring 164 136
Bug Fixing 180 136
Unit Test Generation 154 124
Code Documentation 142 131
Regex Writing 135 119
CI/CD Pipelines 144 120
Frontend Component Design 146 122
Data Analysis 170 124
CSV / Spreadsheet Cleanup 154 133
ETL Scripting 154 128
JSON Extraction 139 131
Bulk Data Labeling 125 129
OCR / Document Parsing 146 131
Table Extraction from PDFs 146 131
Long-Document Summarization 159 137
Short-Form Summarization 123 123
Blog Post Writing 140 121

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

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