MiniMax: MiniMax M3.1 Flash (free) vs Anthropic: Claude Sonnet 5.5
Side-by-side comparison of specs, pricing, benchmark scores, and task rankings. Updated 2026-10-20.
| MiniMax: MiniMax M3.1 Flash (free) | Anthropic: Claude Sonnet 5.5 | |
|---|---|---|
| Vendor | minimax | anthropic |
| Quality Score | 100 | 100 |
| Benchmark Score | - | 96.9 |
| Input Price | Free | $2.00/M |
| Output Price | Free | $10.00/M |
| Context Window | 1,000,000 | 1,000,000 |
| Max Output | 524,288 | 128,000 |
| Tool Calling | ✓ | ✓ |
| Structured Output | ✓ | ✓ |
| Reasoning Mode | ✓ | ✓ |
| Vision | ✓ | ✓ |
| Audio | - | - |
| Benchmark Scores | ||
| ai_index | - | 92.4 |
The verdict
For a sample job of 1 million input tokens and 250,000 output tokens, MiniMax M3.1 Flash (free) costs $0 and Claude Sonnet 5.5 costs $4.50, so MiniMax M3.1 Flash (free) is free for the same work.
Both read up to 1,000,000 tokens at once, roughly 1,500 pages of text.
Only MiniMax M3.1 Flash (free) offers video input.
Across the 20 tasks where they differ, MiniMax M3.1 Flash (free) scores higher on 4 (Code Completion, JSON Extraction, Bulk Data Labeling and others), Claude Sonnet 5.5 on 16 (SQL Generation, Code Review, Code Refactoring and others).
MiniMax M3.1 Flash (free) was released in October 2026 and Claude Sonnet 5.5 in September 2026.
Pick MiniMax M3.1 Flash (free) if you need lower cost or video input; pick Claude Sonnet 5.5 if you need 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.
Who wins by task?
| Task | MiniMax: MiniMax M3.1 Flash (free) | Anthropic: Claude Sonnet 5.5 |
|---|---|---|
| SQL Generation | 134 | 143 |
| Code Review | 132 | 149 |
| Code Completion | 132 | 119 |
| Code Refactoring | 136 | 150 |
| Bug Fixing | 136 | 153 |
| Unit Test Generation | 124 | 135 |
| Code Documentation | 132 | 137 |
| Regex Writing | 120 | 126 |
| CI/CD Pipelines | 120 | 131 |
| Frontend Component Design | 122 | 133 |
| Data Analysis | 124 | 137 |
| CSV / Spreadsheet Cleanup | 134 | 136 |
| ETL Scripting | 128 | 140 |
| JSON Extraction | 132 | 121 |
| Bulk Data Labeling | 130 | 118 |
| OCR / Document Parsing | 131 | 135 |
| Table Extraction from PDFs | 131 | 135 |
| Long-Document Summarization | 138 | 151 |
| Short-Form Summarization | 124 | 118 |
| Blog Post Writing | 122 | 131 |
Scores reflect capability match + benchmark data + pricing for each task. Methodology →