Can you open introcs.cs.princeton.edu from mainland China?
Sometimes.
No recent testsVerdict from 2026-02-14 · 6 mo ago
As of the last test on 2026-02-14 — 6 mo ago — it was partly disrupted in mainland China. We haven't tested it since, so this may have changed.
Access introcs.cs.princeton.edu with GreatFireVPN →Frequently asked questions
Is introcs.cs.princeton.edu blocked in mainland China right now?
We haven't tested introcs.cs.princeton.edu in the last 90 days. As of the last test on 2026-02-14 (6 mo ago), it was partly disrupted in mainland China. Use the Test now button on this page for a fresh measurement.
Why is introcs.cs.princeton.edu blocked in mainland China?
As of the last test on 2026-02-14 — 6 mo ago — it was partly disrupted in mainland China. We haven't tested it since, so this may have changed.
Since when has introcs.cs.princeton.edu been blocked?
GreatFire has recorded interference with introcs.cs.princeton.edu from mainland China since 2016-02-16.
How can I access introcs.cs.princeton.edu from mainland China?
You need a circumvention tool such as a VPN. GreatFireVPN, built by GreatFire, is designed to bypass the Great Firewall and reach sites like introcs.cs.princeton.edu.
http://introcs.cs.princeton.edu · JSON