How to validate a CSV
- Open the file. Suggest from data drafts rules from what is already there: required columns, types, unique IDs and short lists of allowed values.
- Adjust the rules for each column. The report updates as you type.
- Download the report as CSV, and export the rules as JSON to check the next file the same way.
Frequently asked questions
Which rules can I set?
Per column: required, a type (integer, number, date, date and time, boolean, email, URL, UUID or text), a regular expression, unique values, minimum and maximum, length limits and a list of allowed values. For the whole file: required columns and, optionally, no unexpected columns.
How do regular expressions work here?
The pattern must match the whole value, as if it were wrapped in ^ and $. Tick Ignore case to match letters in any case; the same switch applies to allowed values and uniqueness.
Can I reuse my rules?
Yes. Export the rules as a JSON file and import it next time, or share it with a colleague so everyone checks files the same way.
What counts as an empty cell?
A cell that is empty or only spaces. A required column reports it; other rules skip empty cells, so an optional email column only checks the values that are there.