imapsync vs Inbox Hop

imapsync is an IMAP transfer tool for migrating or backing up mailbox accounts. Its command-line software makes incremental, recursive transfers, and a stopped transfer can be restarted without generating duplicates. The software runs on Windows, Mac OS X and Linux, with listed compatibility including Gmail, Office 365, Exchange, Dovecot and Zimbra. The online service offers free mailbox syncs below 3 GB; buying provides unlimited syncs of any size. Buyers also receive a visual interface for installation on a Linux server, though that interface does not yet work on Windows. Staged and tenant-to-tenant moves are supported, including for Microsoft 365 and Google Workspace. The software-only plan is €72 as a one-time purchase; professional support is €144, paid once, as is the Imapsync + support plan. There is no trial version, and purchases carry a 30-day money-back guarantee. The tool cannot migrate contacts or calendars, maintain two-way synchronization between active accounts, or transfer messages to or from a local directory.

Inbox Hop migrates email, calendars, and contacts among Microsoft 365, Google Workspace, and on-premises Exchange. Projects can move data cloud-to-cloud, from cloud to on-premises, or in the reverse direction. Microsoft 365 connections use Exchange Web Services with guided Azure app registration and permission checks. Google Workspace uses Google APIs and service-account domain-wide delegation, avoiding per-mailbox credentials. After scanning, the platform suggests mailbox matches; users can change assignments or create missing destination mailboxes automatically. Run modes include scanning, folder-structure-only copies, full migrations, and incremental delta runs. A full migration consumes one prepaid credit per mailbox regardless of data volume, while scans and delta runs use no credits. On-premises Exchange can connect directly over HTTPS or through a Windows connector that polls outbound HTTPS without inbound firewall rules. Monitoring shows transfer rate, items per minute, health, and chronological logs. Inbox Hop describes encrypted connection secrets, tenant isolation, role separation, permission validation, and append-only audit records. It is intended for organizations changing mail platforms.