CTFlearn
Solve short CTF problems and submit the flags
CTFlearn is a library of capture the flag problems. You pick a challenge, work out the hidden flag, and submit it to score points. The site has hundreds of challenges.
Free · Browser · Beginner
About CTFlearn
It calls itself the most beginner-friendly way to get into hacking, and many problems are short. It suits people who are new to CTFs and want a gentle place to practice before real competitions.
The site runs in the browser and offers a free account. The community talks on Discord, Twitter and Reddit.
On Breakpoint since 23 Oct 2026.