HTTPfy

TWCA certificates on popular websites

TWCA issued 4 of the 8,208 certificates we observed on popular sites in November 2026.

0.0%of observed certificates4 of 8,208

94 daysmedian validity period

0.0%expiring within 30 daysat scan time

100.0%validated for the host name

Validity period

Days between notBefore and notAfter of the leaf certificate.

up to 100 days 75.0%

101 to 200 days 25.0%

201 to 398 days 0.0%

over 398 days 0.0%

TLS versions negotiated

On sites using TWCA (accent) and all sites (grey).

TLSv1.3 75.0%

all sites 84.9%

TLSv1.2 25.0%

all sites 15.1%

About TWCA

Issuer organisation names seen in these certificates: TAIWAN-CA (4).

0.0% of the domains using TWCA publish a CAA record (all sites: 20.7%). A CAA record names the CAs allowed to issue for the domain; any other CA must refuse.

CA site: https://www.twca.com.tw/

Popular sites with a TWCA certificate

momoshop.com.twntu.edu.twcwa.gov.twgigabyte.com

Check one yourself:

Check SSL certificate Look up CAA records HTTP headers

Source: our own scan of November 2026 (2026-11-11), 9,971 of the top 10,000 domains of the Tranco list Y895G that answered in DNS. Method and data.