Check the data type of every column
Drop a CSV or Excel file. Each column gets a type, a confidence score and the cells that break the pattern.
- Runs on your device
- No sign-up
- Works offline after a visit
JSON schema
SQL table
How to check the data type of each column
- Drop a CSV or Excel file, or paste rows from a spreadsheet.
- Read each column card: its type, its confidence and the cells that do not fit.
- Copy the schema as JSON or as an SQL CREATE TABLE.
Questions
How does it decide a column’s type?
It gives every non-empty cell one reading, such as a whole number, a date or an email address. The column takes the reading most of its cells share, and confidence is the share of cells with no problem.
Why is a date marked ambiguous?
If no date in the column has a first or second part above 12, then 03/04/2025 could be 3 April or 4 March. The tool says the order is ambiguous rather than guess.
Why do leading zeros matter?
A zip code or an ID such as 01234 loses its zero when a spreadsheet reads it as a number. Keep such columns as text in your database.
Does it change my file?
No. The file is read in your browser and never uploaded, and nothing is rewritten. The schema is a suggestion to review before you use it.
Reviews
No reviews yet. Be the first.