Online Tool Store
CSV Type Detector
CSV Type Detector shows why a column typed the way it did; the exception rows are usually the whole story. Runs entirely in your browser with no upload and no.
🔒 This tool runs entirely in your browser. Your files are never uploaded to a server.
Data & CSV
CSV Type Detector
Frontend preview — no upload or external service.
Column types
id integer, joined date (ISO), amount decimal — with 3 exceptions: two amount values contain thousands separators and one joined value is empty.
How the CSV Type Detector works
- Paste the CSV including its header row.
- Set the date format if your data is ambiguous — 03/04 is two different dates depending on the convention.
- Read the exception rows first. A column typed as text because of four bad values is the usual reason an import fails.
FAQ
Why is my numeric column detected as text?
Because at least one value is not a number — usually a thousands separator, a currency symbol, a stray space, or an empty string. The exception list shows exactly which rows.
How are ambiguous dates handled?
03/04/2026 is 3 April or 4 March depending on convention, and no amount of inspection resolves it from data alone. Set the format explicitly when the file could be either.
Does this change my file?
No. Detection is read-only and everything happens in the browser, which matters when the CSV is an export containing customer data.
How we compare
| Feature | Online Tool Store | A spreadsheet | A BI platform |
|---|---|---|---|
| Reports exception rows | ✓ | ✗ | ✓ |
| Handles ambiguous dates | ✓ | Guesses | ✓ |
| Nothing uploaded | ✓ | ✓ | ✗ |
| No row limit | Browser memory | Row limit | ✗ |
CSV Type Detector shows why a column typed the way it did; the exception rows are usually the whole story.