How to Detect File Types
🔍 Open the File Type Detector to try every feature described in this guide.
Open File Type Detector →What Is the File Type Detector?
The File Type Detector identifies the type of an uploaded file by inspecting both the file extension and the leading byte signature (magic numbers) where available. Results include the detected type, confidence reasoning, MIME hint, and a link to the appropriate tool for that file type.
Try the File Type Detector — free, private, no install.
Open the Tool →Supported File Types
The detector covers the major types used on this site: CSV, TSV, JSON, XML, Excel (XLSX), DBF, OFX, QFX, QBO, MT940, IIF, SQLite, DuckDB, and Parquet. Unknown or binary files are reported as such with the evidence shown.
Confidence Levels
| Confidence | Meaning |
|---|---|
| High | Both extension and content signature match, or a definitive magic byte signature was found |
| Medium | Extension matches but no signature available, or content matches but extension differs |
| Low | No clear match from either extension or content inspection |
Privacy
All detection is local. Your file never leaves your browser.
For a step-by-step walkthrough see the File Type Detector tutorial.