Have you activated our email validation API and would like to send your file?

The sendfile API allows you to send a file for bulk email validation. The content type needs to be multipart/form-data. Please refer to the C# example for details.

There is no restriction on file size, number of emails, or number of files you can submit using this endpoint. As long as you have the credits in your account to cover the number of emails submitted in the file, your file will be accepted.

Consider activating AutoPay in your ZeroBounce account and ensure you never run out of credits.



URL Parameters

  • Parameter
  • file
    csv or txt file. Byte array contents for the submitted file. The content's header is type of "text/csv".
  • api_key
    Your API Key, found in your account. (Required)
  • return_url
    The URL will be used to call back when the validation is completed. (Optional)
  • email_address_column
    The column index of the email address in the file. Index starts from 1. (Required)
  • first_name_column
    The column index of the first name column. (Optional)
  • last_name_column
    The column index of the last name column. (Optional)
  • gender_column
    The column index of the gender column. (Optional)
  • ip_address_column
    The IP Address the email signed up from. (Optional)
  • has_header_row
    If the first row from the submitted file is a header row. true or false (Optional)
  • remove_duplicate
    If you want the system to remove duplicate emails (true or false, default is true). Please note that if we remove more than 50% of the lines because of duplicates (parameter is true), system will return a 400 bad request error as a safety net to let you know that more than 50% of the file has been modified.
If a return_url was specified in the Multipart Form Data during the send file request, we will POST the following data to the URL when the validation process is complete.

      "file_id": "aaaaaaaa-zzzz-xxxx-yyyy-5003727fffff",
      "file_name": "Your file name.csv", 
      "upload_date": "2023-04-28T15:25:41Z" 



Successful Response

      "success": true,
      "message": "File Accepted",
      "file_name": "Your file name.csv",
      "file_id": "aaaaaaaa-zzzz-xxxx-yyyy-5003727fffff"
Error Response

      "success": false,
      "message": [
          "Error messages"

The ZeroBounce email validation API is one of the most effective tools to keep bad data out of your list. The API can detect and reject more than 30 types of problematic email addresses, thus helping to maintain your email hygiene.

Need help sending your file for bulk email validation? Let us know – our team is available around the clock to assist you.