colorado.edu
Mixed
Results vary across colorado.edu: of 13 URLs tested, 1 is blocked, 3 are disrupted some of the time and 9 load normally. The Great Firewall blocks the connection outright. 233 tests have been run under this domain since 2012-05-28, the most recent on 2026-09-20.
The two are filtered by different means — an unencrypted request by the address and keywords it carries in the clear, an encrypted one by the server name in its TLS handshake — so one working while the other does not is normal.
The site itself
http://colorado.eduBlockedhttps://colorado.eduNot blockedhttp://www.colorado.eduIntermittentPages and subdomains (10)
http://cs.colorado.eduas of 2026Not blockedhttps://lasp.colorado.eduIntermittenthttps://phet.colorado.eduNot blockedhttp://www.cs.colorado.eduas of 2026Not blockedhttps://scholar.colorado.eduas of 2026Not blockedhttps://applied.cs.colorado.eduas of 2026Not blockedhttps://phet.colorado.edu/en/simulations/category/newNot blockedhttps://phet.colorado.edu/en/simulation/legacy/alpha-decayNot blockedhttps://www.colorado.edu/physics/academics/graduate-students/graduate-program-requirements-phdas of 2026Not blockedhttps://phet.colorado.edu/sims/html/balloons-and-static-electricity/latest/balloons-and-static-electricity_en.htmlIntermittentAbout colorado.edu and the Great Firewall
Results vary across colorado.edu: of 13 URLs tested, 1 is blocked, 3 are disrupted some of the time and 9 load normally. The Great Firewall blocks the connection outright. 233 tests have been run under this domain since 2012-05-28, the most recent on 2026-09-20.
Plain HTTP and HTTPS differ here: http://colorado.edu is blocked, https://colorado.edu is not blocked. The two are filtered by different means — an unencrypted request by the address and keywords it carries in the clear, an encrypted one by the server name in its TLS handshake — so one working while the other does not is normal.
A VPN or another circumvention tool routes the request outside mainland China, past the filtering that blocks colorado.edu. GreatFire runs GreatFire VPN; the Analyzer also tests the domains of many VPN and proxy providers, so you can check whether one is reachable before relying on it.
Elsewhere on the site
Most-blocked .edu domainsEvery tested URL under colorado.edu
Each URL's status is its verdict over the last 90 days, the same one its own page headlines.