If you are looking to import MBOX files into Gmail, here are two effective methods to help:
Google Takeout Import: Google Takeout is an official tool provided by Google, making it a secure option. Download your emails in MBOX format using Google Takeout, and then use an email client like Mozilla Thunderbird to import them into Gmail. Simply configure your Gmail account in Thunderbird, drag the MBOX file into your Gmail folder, and the emails will sync.
Third-Party Tools: Dedicated tools like SysTools MBOX to Gmail Importer offer a more streamlined approach. These tools allow you to directly import MBOX files into Gmail without needing an email client. You can also import in bulk, saving time.
Both methods provide reliable solutions depending on your preference for manual control or automated ease.