K-9 Mail — Email Client (Open Source)

K-9 Mail is an open-source Email Client solution from K-9 project. Compare it against 51 other Email Client tools on FreeSoftwareX — by features, licensing and price — and request a quote or demo free in 2026.

What is K-9 Mail?

K-9 Mail is open source — its source code is publicly available and free to use, modify and self-host, usually with an active community and no licensing fees. It is categorised under Email Client and published by K-9 project. Buyers typically evaluate K-9 Mail when they need a dependable Email Client option and want to weigh the trade-offs between free, open-source and paid tools before committing.

• Category: Email Client
• Brand: K-9 project
• License: Open Source

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Frequently asked questions

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