EXCEL TUTORIAL · FREE TOOLS
Contents
CSV Validator Online
Free online tool · No signup · Runs in your browser
Check CSV data against your explicit header, type, and blank-value rules.
Your data stays in this browser tool. No account or upload to a processing service required.
Instructions
- Enter one Header:type:required or Header:type:optional rule per line.
- Types are text, number, integer, date, email, and boolean.
- Click Validate CSV and download the row/column/reason report.
Understanding your result
The sample Age value not-a-number should fail a numeric age rule, while 32 should pass. A successful report means the input meets your entered rules. It does not establish that the destination accepts every field or that an email address exists.
What to do if you have a problem
If a header is reported missing, compare its exact name with your schema line. If optional values fail, optional permits blanks but still checks nonblank entries. Check delimiter and row widths when errors spread across otherwise valid columns, then rerun after correcting the source.
What to know before using the result
Generic schema validation, not maintained destination templates. Every schema header must exist; optional allows blank values. Dates require valid YYYY-MM-DD in years 0001-9999; email checks basic format only; booleans accept true/false/0/1. Integer values must be safely representable. Maximum 2 MB and 20,000 input/report rows. Ragged rows are reported.
These tools work with pasted text or supported CSV files rather than Excel workbook files. CSV exports contain values and do not preserve workbook formatting, formulas or multiple worksheets. Formula builders produce formula text to use in Excel. Data processing runs in the browser tool.
Try an example
Name,Age,Email Alice,32,alice@example.com Bob,not-a-number,bob@example.com
Summary
Correct the reported row and column issues, then validate again against the rules required for your import.