Shoviv IMAP Backup Tool is the best tool for backing up IMAP emails to PST, EML, MSG, MBOX, and HTML formats. It's helpful to back up messages from all IMAP domains like Gmail, Yandex, Rediffmail, Yahoo, Hotmail, AOL, etc. The interface for this solution is simple enough that even anyone who is not a tech-savvy user can use the tool and back up all IMAL email information. Download the trial version of the IMAP software to evaluate the tool before purchasing.
Software Page: https://www.shoviv.com/imap-backup-and-restore.html
If you're still looking for the most cost-effective method to backup IMAP emails, Download The Shoviv Backup tool. It can make backups of mail that originate from Gmail, Yandex, Rediffmail, Yahoo, Hotmail, AOL, and various other IMAP-compatible email servers, without alteration. It allows users the option of using it with no technical knowledge.

It allows users to backup emails using an unlimited number of IMAP accounts with complete precision. The size of the file is not an issue when backing up IMAP emails so that users can save any size of the file with no difficulty. The program lets users select the format in which the backup should be made IMAP database of emails. Users can save IMAP emails to PST, EML, MSG, MBOX, HTML, and many other formats.
For Gmail backup: https://www.shoviv.com/gmail-backup-tool.html