Welcome to BulkVerifier, an efficient multi-threaded application for checking e-mail addresses and domain availability. Quickly and easily verifies email addresses, huge domains and clean up your mailing / domain list. A powerful advanced bulk domain and email validation tool. BulkVerifier offers you two processing modes fast and deep. In its fast mode BulkVerifier works extremely fast being able to process mailing lists containing dozens of millions of e-mail addresses at a speed of several thousands addresses per second. This mode does not ensure the highest accuracy of checking/cleaning but is optimal by expended time and traffic and provides quite sufficient results. We recommend the fast processing mode of BulkVerifier as a high-speed tool for sifting obvious rubbish out of large mailing lists containing millions of e-mail addresses. In its deep mode (default), BulkVerifier works significantly slower but provides much more precise results. Optimal data amount for this mode is 70...100 thousand e-mail addresses. We recommend the deep processing mode of BulkVerifier as a slow but high-quality tool for checking of not very large mailing lists. BulkVerifier can process both plain list of e-mail addresses / domains where each line contains one item and files of more complex structure like CSV file where lines represents multi-field records of the same structure (i. e. containing the same fields separated with the same delimiter). For example, you can export a worksheet of an MS Excel file to check availability of e-mail addresses/domains listed there. It’s supposed that one line of an incoming file contains one e-mail address and/or one domain.