IONOS / 1&1
Registrar DNS Serves 96,086 new-gTLD domains across 143 TLDs, 2.48% of all domains whose nameservers we can attribute. www.ionos.com/
How domains are attributed here
A domain counts towards IONOS / 1&1 when one of its nameservers ends in one of these suffixes. Matching is on the name in the zone's NS records only — nothing is resolved or fetched. Listed by weight, which is the order the classifier tries them in so a specific suffix beats a broader one.
| Nameserver suffix | Weight |
|---|---|
| 1and1-dns.com | 10 |
| ui-dns.biz | 10 |
| ui-dns.com | 10 |
| ui-dns.de | 10 |
| ui-dns.org | 10 |
Where its domains are
| .app | 39,312 | 40.91% |
|---|---|---|
| 4,040 | 4.2% | |
| .solutions | 3,070 | 3.2% |
| .media | 2,157 | 2.24% |
| .services | 2,146 | 2.23% |
| .academy | 2,088 | 2.17% |
| .agency | 2,058 | 2.14% |
| .nyc | 1,533 | 1.6% |
| .events | 1,471 | 1.53% |
| .care | 1,269 | 1.32% |
| Other133 more TLDs | 36,942 | 38.45% |
The ten largest of 143 TLDs, with the rest combined; all of them are in the table below.
Nameservers in use
as of 18 Aug 2026The hostnames actually found in the zones, with how many domains name each. The suffixes above are the rule; these are what the rule matched. Counted across all gTLDs rather than the current scope, since the aggregate is built in one pass over every zone. Showing the fifteen largest.
| Nameserver | Domains | Share of these |
|---|---|---|
| ns-de.1and1-dns.com | 28,937 | |
| ns1045.ui-dns.biz | 22,710 | |
| ns1016.ui-dns.biz | 13,780 | |
| ns1017.ui-dns.biz | 13,324 | |
| ns1021.ui-dns.biz | 13,132 | |
| ns1018.ui-dns.biz | 13,021 | |
| ns1019.ui-dns.biz | 12,946 | |
| ns1023.ui-dns.biz | 12,111 | |
| ns1020.ui-dns.biz | 11,880 | |
| ns1022.ui-dns.biz | 11,805 | |
| ns1024.ui-dns.biz | 11,642 | |
| ns-us.1and1-dns.com | 11,641 | |
| ns1025.ui-dns.biz | 11,582 | |
| ns1027.ui-dns.biz | 11,243 | |
| ns1018.ui-dns.com | 10,738 |
Shares are of the 210,492 domains on these 15 nameservers, not of the provider's 96,086.
Data currency. Domain counts on this page are from zone files dated and refresh daily. Registrar figures are from ICANN's monthly registry reports for April 2026, which ICANN publishes about three months in arrears; zone files contain no registrar information, so no fresher source exists. Full detail on methodology and live pipeline status.