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~/dnsniffer/issuers/microsoft·rank #57

▸ How many domains does Microsoft secure?

3,547

active domains whose current TLS certificate was issued by Microsoft, as of - 0.00% of all attributed domains.

# rank #57 of all CAs ▼ 4 in 30d# all records held: 3,762# subdomains: 26# intermediates: 17# United States
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~/issuers/microsoft/history·active domains
3,547
domains secured by Microsoft on 2026-10-15 · ▲ +1,221 (+52.49%) since 2025-06-30
2.2K2.6K3.0K3.3K3.7K2025-06-30: 2,326 active2025-07-31: 3,449 active2025-08-31: 3,452 active2025-09-30: 3,462 active2025-10-31: 3,462 active2025-11-30: 3,462 active2025-12-31: 3,545 active2026-01-31: 3,559 active2026-02-28: 3,559 active2026-03-31: 3,559 active2026-04-30: 3,575 active2026-05-31: 3,577 active2026-06-30: 3,577 active2026-07-31: 3,578 active2026-08-31: 3,577 active2026-09-01: 3,571 active2026-09-02: 3,545 active2026-09-03: 3,523 active2026-09-04: 3,528 active2026-09-05: 3,527 active2026-09-06: 3,525 active2026-09-07: 3,522 active2026-09-08: 3,519 active2026-09-09: 3,509 active2026-09-10: 3,503 active2026-09-11: 3,489 active2026-09-12: 3,481 active2026-09-13: 3,473 active2026-09-14: 3,474 active2026-09-15: 3,472 active2026-09-16: 3,457 active2026-09-17: 3,460 active2026-09-18: 3,459 active2026-09-19: 3,450 active2026-09-20: 3,450 active2026-09-21: 3,450 active2026-09-22: 3,448 active2026-09-23: 3,484 active2026-09-24: 3,525 active2026-09-25: 3,523 active2026-09-26: 3,525 active2026-09-27: 3,504 active2026-09-28: 3,487 active2026-09-29: 3,486 active2026-09-30: 3,475 active2026-10-01: 3,477 active2026-10-02: 3,480 active2026-10-03: 3,479 active2026-10-04: 3,471 active2026-10-05: 3,460 active2026-10-06: 3,460 active2026-10-07: 3,454 active2026-10-08: 3,453 active2026-10-09: 3,448 active2026-10-10: 3,445 active2026-10-11: 3,444 active2026-10-12: 3,510 active2026-10-13: 3,519 active2026-10-14: 3,566 active2026-10-15: 3,547 active2025-06-302026-10-15

# y-axis starts at 2.2K, 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
▲ +2.16%
+75 domains
90 days
▼ -0.84%
-30 domains
1 year
▲ +2.46%
+85 domains
# intermediate CAs
Intermediate certificate authorities operating under Microsoft, with the number of active domains each currently secures.
intermediatecountrydomains
Microsoft TLS G2 RSA CA OCSP 10United States1,188
Microsoft TLS G2 RSA CA OCSP 02United States987
Microsoft TLS G2 RSA CA OCSP 04United States627
Microsoft TLS G2 RSA CA OCSP 16United States524
Microsoft Azure RSA TLS Issuing CA 03United States112
Microsoft Azure RSA TLS Issuing CA 07United States63
Microsoft Azure RSA TLS Issuing CA 08United States21
Microsoft Azure RSA TLS Issuing CA 04United States16
MSFT RS256 CA-1United States9
Microsoft RSA TLS Issuing EOC CA 01United States0
Microsoft RSA TLS Issuing EOC CA 02United States0
Microsoft RSA TLS Issuing AOC CA 02United States0
Microsoft TLS G1 RSA CA 01United States0
Microsoft RSA TLS Issuing AOC CA 01United States0
Microsoft ECC TLS Issuing AOC CA 01United States0
Microsoft ECC TLS Issuing EOC CA 01United States0
MSFT BALT RS256 CAUnited States0
# faq
? How many domains does Microsoft secure?
Microsoft is the certificate authority for 3,547 active domains as of October 15, 2026 - 0.00% of every domain DNSniffer can attribute to an issuer.
? Is Microsoft gaining or losing market share?
The number of domains secured by Microsoft has grown by 2.46% over the last year (+85 domains).
? Which intermediate CAs does Microsoft sign from?
We have seen 17 intermediates under Microsoft, the busiest being “Microsoft TLS G2 RSA CA OCSP 10” with 1,188 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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