As of October 11, 2026, Proton Mail is used by 106,824 websites in the TechLeads index: 65.1% of all Secure Email detections, the 1st most-used of 65 Secure Email technologies.
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Citation
TechLeads. "Proton Mail Customers and Market Share." Data as of October 11, 2026. https://techleads.fyi/technology/proton-mail/market-shareHTML link
<a href="https://techleads.fyi/technology/proton-mail/market-share">Proton Mail market share (TechLeads data)</a>Websites using each technology in the TechLeads index, and its share of all Secure Email detections.
| # | Technology | Websites | Share |
|---|---|---|---|
| 1 | Proton Mail | 106,824 | 65.1% |
| 2 | MailInBlack | 8,453 | 5.2% |
| 3 | Sophos | 8,143 | 5.0% |
| 4 | CDNS Network | 7,266 | 4.5% |
| 5 | Hushmail | 4,249 | 2.6% |
| 6 | Skymail | 4,042 | 2.5% |
| 7 | Securence | 2,558 | 1.6% |
In HTTP Archive's monthly crawl of public websites, Proton Mail was detected on 71,216 pages in September 2026, up 29.8% from a year earlier. Among the 1,000 most-visited sites, it appeared on 37. HTTP Archive is a separate dataset from the TechLeads index, so its numbers are not added to ours.
Same month, other Webmail technologies in HTTP Archive: Apple iCloud Mail 2,030,565, RoundCube 4,502, Zimbra 3,928, Outlook Web App 468, SquirrelMail 63.
Based on country-code domains (such as .de or .co.uk); websites on .com and other generic domains are not assigned a country.
See all 106,824 websites using Proton Mail or download the full list as a CSV for $29.
TechLeads scans public websites and detects Proton Mail from signals in the page HTML, scripts, cookies, HTTP headers and DNS records. Market share is Proton Mail's website count divided by the website counts of all Secure Email technologies we track; a site using two Secure Email tools counts for both. Counts were last refreshed on October 11, 2026 and update daily.
| 8 | SpamTitan | 2,371 | 1.5% |
| 9 | Migadu | 2,295 | 1.4% |
| 10 | MailGuard | 2,264 | 1.4% |
| 11 | Mailcheap | 2,078 | 1.3% |
| 12 | Spam Hero | 1,534 | 0.95% |
| 13 | Enguard | 1,088 | 0.67% |
| 14 | ZoneEdit MX | 1,034 | 0.64% |
| 15 | TOPSEC | 1,015 | 0.63% |
| 16 | Spamtador | 986 | 0.61% |
| 17 | MailRoute | 873 | 0.54% |
| 18 | Pobox | 578 | 0.36% |
| 19 | StartMail | 516 | 0.32% |
| 20 | Paubox | 486 | 0.30% |
| 21 | Agari | 469 | 0.29% |
Rows link to each competitor's market share page where one exists. The table lists the 21 most-used technologies; ranks are by website count.