As of October 8, 2026, IONOS Mail is used by 690,910 websites in the TechLeads index: 5.6% of all Email detections, the 5th most-used of 133 Email technologies.
Quoting these numbers? Credit TechLeads with a link to this page.
Citation
TechLeads. "IONOS Mail Customers and Market Share." Data as of October 8, 2026. https://techleads.fyi/technology/ionos-mail/market-shareHTML link
<a href="https://techleads.fyi/technology/ionos-mail/market-share">IONOS Mail market share (TechLeads data)</a>Websites using each technology in the TechLeads index, and its share of all Email detections.
| # | Technology | Websites | Share |
|---|---|---|---|
| 1 | Google Workspace | 3,246,665 | 26.1% |
| 2 | Microsoft 365 | 2,701,100 | 21.7% |
| 3 | Hostinger Mail | 938,104 | 7.6% |
| 4 | MailChimp | 820,056 | 6.6% |
| 5 | IONOS Mail | 690,910 | 5.6% |
| 6 | Mailgun | 664,476 | 5.3% |
| 7 | Amazon SES | 634,305 |
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 690,910 websites using IONOS Mail or download the full list as a CSV for $29.
TechLeads scans public websites and detects IONOS Mail from signals in the page HTML, scripts, cookies, HTTP headers and DNS records. Market share is IONOS Mail's website count divided by the website counts of all Email technologies we track; a site using two Email tools counts for both. Counts were last refreshed on October 8, 2026 and update daily.
| 5.1% |
| 8 | Sendgrid | 522,101 | 4.2% |
| 9 | Yandex Mail | 194,429 | 1.6% |
| 10 | Sendinblue | 190,288 | 1.5% |
| 11 | MailJet | 183,055 | 1.5% |
| 12 | Lolipop Mail | 136,572 | 1.1% |
| 13 | ActiveCampaign | 131,218 | 1.1% |
| 14 | DMARC None | 104,042 | 0.84% |
| 15 | Creativ.eMail | 103,066 | 0.83% |
| 16 | Jimdo Mail | 97,951 | 0.79% |
| 17 | MailerLite | 88,964 | 0.72% |
| 18 | SparkPost | 82,422 | 0.66% |
| 19 | ZXCS | 76,420 | 0.62% |
| 20 | LiveIntent | 72,726 | 0.59% |
| 21 | DKIM | 64,535 | 0.52% |
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.