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Cold email CSV validator
Check pasted CSV structure, email syntax, duplicate headers and spreadsheet-formula risks locally in your browser.
Prepare your inputs
Paste a small CSV sample with an Email header. Quoted commas, escaped quotation marks and embedded newlines are parsed as CSV fields. The utility does not upload data or create contacts.
Runs in this browser. Inputs are not sent by this tool or saved in browser storage. Start with the fictional example; use redacted text for reviews.
How it works
The review checks field counts, nonempty unique headers, approximate email syntax and repeated normalized addresses. It also counts cells that deserve review before opening the file in a spreadsheet.
Worked example
Email,Name followed by a row with three unquoted comma-separated fields produces a column-count warning. A comma inside a correctly quoted name remains part of one field.
Limits and interpretation
The limit is 100,000 characters. Syntax is not mailbox verification, permission or a guarantee of successful Zintara import. Logical row numbers can differ from physical lines when a quoted field contains a newline.
Examples are synthetic, not customer results. Zintara practical guide library