Google: Gemini 3.5 Flash vs Google: Gemini 3.1 Flash Lite Preview
Side-by-side comparison of specs, pricing, benchmark scores, and task rankings. Updated 2026-11-07.
| Google: Gemini 3.5 Flash | Google: Gemini 3.1 Flash Lite Preview | |
|---|---|---|
| Vendor | ||
| Quality Score | 100 | 100 |
| Benchmark Score | 84.2 | - |
| Input Price | $1.50/M | $0.25/M |
| Output Price | $9.00/M | $1.50/M |
| Context Window | 1,048,576 | 1,048,576 |
| Max Output | 65,536 | 65,536 |
| Tool Calling | ✓ | ✓ |
| Structured Output | ✓ | ✓ |
| Reasoning Mode | ✓ | ✓ |
| Vision | ✓ | ✓ |
| Audio | ✓ | ✓ |
| Benchmark Scores | ||
| ai_index | 82.8 | - |
| ai_index_agentic | 61.8 | - |
| ai_index_coding | 100.0 | - |
The verdict
For a sample job of 1 million input tokens and 250,000 output tokens, Gemini 3.1 Flash Lite Preview costs $0.62 and Gemini 3.5 Flash costs $3.75, so Gemini 3.1 Flash Lite Preview is about 6.0 times cheaper for the same work.
Both read up to 1,048,576 tokens at once, roughly 1,573 pages of text.
Across the 20 tasks where they differ, Gemini 3.5 Flash scores higher on 17 (SQL Generation, Code Review, Code Refactoring and others), Gemini 3.1 Flash Lite Preview on 3 (Code Completion, Bulk Data Labeling, Short-Form Summarization).
Gemini 3.5 Flash was released in May 2026 and Gemini 3.1 Flash Lite Preview in March 2026.
Pick Gemini 3.5 Flash if you need the stronger all-round task scores; pick Gemini 3.1 Flash Lite Preview if you need lower cost.
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?
| Task | Google: Gemini 3.5 Flash | Google: Gemini 3.1 Flash Lite Preview |
|---|---|---|
| SQL Generation | 168 | 133 |
| Code Review | 164 | 132 |
| Code Completion | 119 | 131 |
| Code Refactoring | 162 | 136 |
| Bug Fixing | 176 | 136 |
| Unit Test Generation | 152 | 124 |
| Code Documentation | 141 | 131 |
| Regex Writing | 133 | 119 |
| CI/CD Pipelines | 143 | 120 |
| Frontend Component Design | 145 | 122 |
| Data Analysis | 167 | 124 |
| CSV / Spreadsheet Cleanup | 153 | 133 |
| ETL Scripting | 152 | 128 |
| JSON Extraction | 138 | 131 |
| Bulk Data Labeling | 124 | 129 |
| OCR / Document Parsing | 146 | 131 |
| Table Extraction from PDFs | 146 | 131 |
| Long-Document Summarization | 157 | 137 |
| Short-Form Summarization | 121 | 123 |
| Blog Post Writing | 138 | 121 |
Scores reflect capability match + benchmark data + pricing for each task. Methodology →