Most lists arrive as a CRM export, a spreadsheet or a plain dump of addresses. ZapBounce reads all three. Upload a CSV or an Excel XLSX file with as many columns as you like, or a TXT file with one address per line. A TXT file needs no setup at all.
You don't have to tell us which column holds the address. ZapBounce scans the first few hundred rows for address-shaped values and picks the email column. If your file has two candidates, say work_email and personal_email, you name the one you mean. Text encoding is detected across UTF-8, Latin-1 and UTF-16, so accented names come back intact.
Results come back in the format you choose, CSV or XLSX. Your columns stay exactly as they were, and the result fields sit beside them: result, reason, the role, disposable and free_provider flags, did_you_mean, smtp_code, billed and checked_at. Filter the result column on catch_all to send those rows as their own segment. The result codes reference explains each value.
A few habits save a re-upload. Quote any field that contains a comma, or the columns shift and the verdict lands against the wrong record. Check the header setting, since a header row read as data turns into one invalid address. Compress a file above about 50 MB with gzip, which the upload accepts.
Working from Google Sheets or a CRM? Export the sheet or the contact view as CSV, verify it on the bulk page, then import the file back. Duplicates in the file are never billed, nor are unknown results, and 10,000 checks cost $25. Developers can skip files entirely and send up to 100,000 addresses as JSON through the batch endpoint.
Related questions
Can I upload an Excel file for email verification?
Yes. ZapBounce accepts XLSX files and returns results as XLSX or CSV, with every original column kept. Name the email column if the sheet has more than one address column.
Do I need to remove other columns before uploading?
No. Keep every column: names, company, owner, lead source. ZapBounce carries them through to the output untouched and adds the result fields beside each row.
What is the largest list I can verify?
Large lists go through the file upload, which streams the file instead of packing it into one request. Gzip a file above about 50 MB before you upload it. The JSON batch endpoint takes up to 100,000 addresses per request.
Can I verify a Google Sheet directly?
Export the sheet as CSV, upload it, then import the results back into a new tab. The file keeps your columns in order, so the result column lines up with your rows.