Fossa icon
End-to-end S/MIME solution for Gmail available on
Web and Android
Compatible with
MS Outlook, Thunderbird, iOS Mail, Android Mail (with CipherMail)
Fossa Guard
Fossa Guard Pro ($1.99/month)
S/MIME certificate
Fossa only
Sign & Encrypt email
Certificate Management
S/MIME certificate registry
Multiple private keys
Send mail as
Intelligent Security
Encryption and Signing
Certificate Management

Fossa Guard has own autonomous
Compose and View dialogs to avoid
unsecured email content auto-saving.
Private key is protected by a pass-phrase
and stored in encrypted PKCS#12 archive.

Fossa Guard provides ability
to Sign and to Encrypt your emails
including attachments. Certificates hierarchy
popup menu helps User to decide
about trust level.

Fossa Guard allows User to manage
trusted and end-user certificates inside Chrome
storage synchronized across all your devices.
Fossa Guard Pro makes possible
to import and manage private key
and certificate issued by any CA.

Free S/MIME certificate
Certification Authority
Ease of use issues
free and renewable X.509 certificate
upon Certificate Signing Request (CSR)
for personal S/MIME mailing. is a lightweight Certification
Authority (CA) with an online S/MIME
certificate registry and CRL support. provides seamless integration
with Fossa Guard for secure
certificate (re-)enrollment. does not require
any registration except valid Google account
to start S/MIME mailing.
Fossa Guard Pro supports Send As accounts
making possible to use any email address.

Fossa Team has designed the solution with the only main goal to supply Gmail users with privacy via industry-grade email encryption (S/MIME) integrated into the web browser.
Please read Fossa Privacy Policy to learn more about personal information processing.

Fossa Team is proud to announce beta of S/MIME mailing solution according to the Terms and Conditions
Please contact for additional information

Google®, Google Chrome®, GMail®, Android® are trademarks of Google, Inc
Microsoft®, Microsoft Outlook ® are trademarks of Microsoft Corporation
Apple®, iOS® are trademarks of Apple, Inc
Mozilla®, Mozilla Thunderbird® are trademarks of Mozilla Foundation
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