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~/dnsniffer/issuers/certum·rank #13

▸ How many domains does Certum secure?

159,633

active domains whose current TLS certificate was issued by Certum, as of - 0.07% of all attributed domains.

# rank #13 of all CAs# all records held: 161,340# subdomains: 0# intermediates: 8# Poland
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~/issuers/certum/history·active domains
159,633
domains secured by Certum on 2026-10-15 · ▲ +107,984 (+209.07%) since 2025-06-30
38.7K72.2K105.6K139.1K172.6K2025-06-30: 51,649 active2025-07-31: 86,696 active2025-08-31: 86,968 active2025-09-30: 87,824 active2025-10-31: 87,824 active2025-11-30: 87,824 active2025-12-31: 107,208 active2026-01-31: 113,199 active2026-02-28: 113,199 active2026-03-31: 113,199 active2026-04-30: 128,887 active2026-05-31: 133,847 active2026-06-30: 138,144 active2026-07-31: 141,522 active2026-08-31: 141,528 active2026-09-01: 141,776 active2026-09-02: 142,268 active2026-09-03: 142,792 active2026-09-04: 143,096 active2026-09-05: 143,405 active2026-09-06: 143,580 active2026-09-07: 143,813 active2026-09-08: 144,524 active2026-09-09: 145,215 active2026-09-10: 145,805 active2026-09-11: 146,181 active2026-09-12: 146,454 active2026-09-13: 146,717 active2026-09-14: 147,324 active2026-09-15: 147,892 active2026-09-16: 148,376 active2026-09-17: 148,797 active2026-09-18: 149,501 active2026-09-19: 149,845 active2026-09-20: 150,108 active2026-09-21: 150,463 active2026-09-22: 151,117 active2026-09-23: 151,662 active2026-09-24: 152,861 active2026-09-25: 153,222 active2026-09-26: 153,351 active2026-09-27: 153,415 active2026-09-28: 153,638 active2026-09-29: 154,205 active2026-09-30: 154,794 active2026-10-01: 155,089 active2026-10-02: 155,376 active2026-10-03: 155,518 active2026-10-04: 155,595 active2026-10-05: 155,542 active2026-10-06: 155,929 active2026-10-07: 156,077 active2026-10-08: 156,418 active2026-10-09: 157,104 active2026-10-10: 157,393 active2026-10-11: 157,628 active2026-10-12: 157,811 active2026-10-13: 158,592 active2026-10-14: 158,981 active2026-10-15: 159,633 active2025-06-302026-10-15

# y-axis starts at 38.7K, not zero - domain counts move by fractions of a percent a day. Dashed segments are estimated: reconstructed from certificate first-seen dates before daily snapshots began, not measured on the day.

# change over time
30 days
▲ +7.94%
+11,741 domains
90 days
▲ +15.56%
+21,489 domains
1 year
▲ +81.76%
+71,809 domains
# intermediate CAs
Intermediate certificate authorities operating under Certum, with the number of active domains each currently secures.
intermediatecountrydomains
Certum DV TLS G2 R39 CAPoland154,179
XinNet DV TLS CA-3,158
Certum OV TLS G2 R39 CAPoland2,011
Certum EV TLS G2 R39 CAPoland285
Certum Extended Validation RSA CAPoland0
Certum DV TLS G3 R39 CAPoland0
Certum EV TLS G3 R39 CAPoland0
Certum OV TLS G3 R39 CAPoland0
# faq
? How many domains does Certum secure?
Certum is the certificate authority for 159,633 active domains as of October 15, 2026 - 0.07% of every domain DNSniffer can attribute to an issuer.
? Is Certum gaining or losing market share?
The number of domains secured by Certum has grown by 81.76% over the last year (+71,809 domains).
? Which intermediate CAs does Certum sign from?
We have seen 8 intermediates under Certum, the busiest being “Certum DV TLS G2 R39 CA” with 154,179 domains. The full list, with per-intermediate counts, is on this page.
? Where does this number come from?
DNSniffer ingests Certificate Transparency logs continuously and records the issuer of the most recent certificate seen for each domain, then snapshots the per-issuer count once a day. It measures how much of the live web a CA currently secures, not how many certificates it has issued over its lifetime.
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