Compare software

Gpg4win vs FlowCrypt: catalog facts
Gpg4win	FlowCrypt
Free Free software, funded by donations and public contracts.	Freemium Free extension for individuals, with paid business plans listed on the pricing page.
Windows	Browser extension
Kleopatra gives GnuPG a real key manager instead of a command line Integrates with Outlook through GpgOL and with Explorer through GpgEX	Works inside the normal Gmail interface Encrypts both messages and attachments
Windows only OpenPGP key management is genuinely hard, and the concepts do not hide well behind a GUI	Built around Gmail rather than other mail providers Business features require a paid plan
Downloadable app	Browser extension
Open source	Closed source
License: GPL-2.0	License not stated
No account needed	Not stated if an account is needed
Works offline	Needs internet
Official website Full listing and sources Checked September 20, 2026	Official website Full listing and sources Checked September 24, 2026

Catalog facts only. Anything “not stated” is unconfirmed. Check full listings for details.