Webmail
Who left Proton Mail, and who still runs it
1,289 websites in the top 1M run Proton Mail, observed directly from the rendered page in the July 2026 crawl.
62
stopped running it that month
0
of those are 11–500 employees
643
adopted it in the last year
Confirmed across two consecutive crawls, not a single month. Build the list →
Some companies running Proton Mail
Every row in a full list carries the prospect's whole detected stack.
Not currently available as a list.
What else they run
Cloudflare 79%Open Graph 74%HTTP/3 59%Google Analytics 59%jQuery 47%HSTS 47%Cloudflare Browser Insights 40%Priority Hints 38%PHP 37%Google Tag Manager 36%
Share of a 1,289-domain sample of Proton Mail users that also run each.