It was met with enough response that after three days they needed to temporarily suspend beta signups to expand server capacity. On May 16, 2014, Proton Mail entered into public beta. Acquiring no fewer than 2 million users by 2017, membership grew to almost 70 million by 2022.

Initial membership was by invitation only however, beginning in March 2016, Proton Mail was opened to the public. Although the default account setup is free, the service is sustained by optional paid services. Proton Mail received initial funding through a crowdfunding campaign. The company also operates Proton VPN, Proton Drive and Proton Calendar. Proton Mail is run by Proton AG (formerly Proton Technologies), which is based in the Canton of Geneva. The service can be accessed through a webmail client, the Tor network, or dedicated iOS and Android apps. It uses client-side encryption to protect email content and user data before they are sent to Proton Mail servers, unlike other common email providers such as Gmail and. Proton Mail (previously written as ProtonMail) is an end-to-end encrypted email service founded in 2013 in Geneva, Switzerland. protonmailrmez3lotcci pshtkleegetolb73fuirg j7r4o4vfu7ozyd.onion ( Accessing link help).

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