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~/dnsniffer/issuers/japan-registry-services-co·rank #28

▸ How many domains does Japan Registry Services Co secure?

21,367

active domains whose current TLS certificate was issued by Japan Registry Services Co, as of - 0.01% of all attributed domains.

# rank #28 of all CAs ▼ 3 in 30d# all records held: 22,441# subdomains: 3,425# intermediates: 2# Japan
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~/issuers/japan-registry-services-co/history·active domains
21,367
domains secured by Japan Registry Services Co on 2026-10-15 · ▲ +6,654 (+45.23%) since 2025-06-30
12.6K18.0K23.4K28.8K34.2K2025-06-30: 14,713 active2025-07-31: 29,814 active2025-08-31: 29,913 active2025-09-30: 29,913 active2025-10-31: 29,913 active2025-11-30: 29,913 active2025-12-31: 31,323 active2026-01-31: 31,709 active2026-02-28: 31,709 active2026-03-31: 31,709 active2026-04-30: 32,008 active2026-05-31: 32,109 active2026-06-30: 32,109 active2026-07-31: 32,109 active2026-08-31: 32,109 active2026-09-01: 31,158 active2026-09-02: 30,133 active2026-09-03: 28,127 active2026-09-04: 27,493 active2026-09-05: 27,299 active2026-09-06: 27,285 active2026-09-07: 27,209 active2026-09-08: 26,927 active2026-09-09: 26,704 active2026-09-10: 26,582 active2026-09-11: 26,442 active2026-09-12: 26,316 active2026-09-13: 26,301 active2026-09-14: 26,241 active2026-09-15: 26,065 active2026-09-16: 25,852 active2026-09-17: 25,558 active2026-09-18: 25,367 active2026-09-19: 25,261 active2026-09-20: 25,244 active2026-09-21: 25,217 active2026-09-22: 25,181 active2026-09-23: 25,154 active2026-09-24: 26,029 active2026-09-25: 25,864 active2026-09-26: 25,715 active2026-09-27: 25,691 active2026-09-28: 25,618 active2026-09-29: 25,333 active2026-09-30: 25,177 active2026-10-01: 24,476 active2026-10-02: 24,063 active2026-10-03: 23,852 active2026-10-04: 23,833 active2026-10-05: 23,040 active2026-10-06: 22,794 active2026-10-07: 22,590 active2026-10-08: 22,387 active2026-10-09: 22,177 active2026-10-10: 22,021 active2026-10-11: 21,993 active2026-10-12: 21,975 active2026-10-13: 21,877 active2026-10-14: 21,648 active2026-10-15: 21,367 active2025-06-302026-10-15

# y-axis starts at 12.6K, 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
▼ -18.02%
-4,698 domains
90 days
▼ -33.45%
-10,742 domains
1 year
▼ -28.57%
-8,546 domains
# intermediate CAs
Intermediate certificate authorities operating under Japan Registry Services Co, with the number of active domains each currently secures.
intermediatecountrydomains
JPRS Domain Validation Authority - G4Japan20,611
JPRS Organization Validation Authority - G4Japan756
# faq
? How many domains does Japan Registry Services Co secure?
Japan Registry Services Co is the certificate authority for 21,367 active domains as of October 15, 2026 - 0.01% of every domain DNSniffer can attribute to an issuer.
? Is Japan Registry Services Co gaining or losing market share?
The number of domains secured by Japan Registry Services Co has shrunk by 28.57% over the last year (-8,546 domains).
? Which intermediate CAs does Japan Registry Services Co sign from?
We have seen 2 intermediates under Japan Registry Services Co, the busiest being “JPRS Domain Validation Authority - G4” with 20,611 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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