Repository to index interesting Capture The Flag online tools.
https://ctftime.org/
https://www.hackthebox.eu/
https://ctflearn.com/
https://atenea.ccn-cert.cni.es/
https://unaalmes.hispasec.com
https://www.root-me.org/
https://ctf365.com/
https://requestbin.fullcontact.com/
https://reqbin.com/
https://beautifier.io/
http://jsonviewer.stack.hu/
https://pentest-tools.com/
https://tableconvert.com/
https://www.rdtoc.com/tools/jmespath
https://www.rdtoc.com/tools/jsonpath
https://onlinedisassembler.com/
http://www.javadecompilers.com/
https://www.hybrid-analysis.com/
https://any.run/
https://gchq.github.io/CyberChef/
https://www.dcode.fr/tools-list#cryptography
http://multiencoder.com/
https://hexed.it/
https://md5online.es/
https://hashgenerator.de/
https://cryptii.com/
https://geocaching.dennistreysa.de/multisolver/index.html
https://quipqiup.com/
http://www.crypo.com/
http://www.malbolge.doleczek.pl/
http://rumkin.com/tools/cipher/
https://summersidemakerspace.ca/projects/enigma-machine/
https://www.guballa.de/vigenere-solver
https://futureboy.us/stegano/
http://exif.regex.info/exif.cgi
https://incoherency.co.uk/image-steganography/
https://yndi.github.io/darkjpeg/
https://morsecode.scphillips.com/labs/audio-decoder-adaptive/
https://www.bertnase.de/npiet/npiet-execute.php
https://inteltechniques.com/menu.html
https://ciberpatrulla.com/links/
https://osintframework.com/
https://ctf.courgettes.club/
https://ctftime.org/writeups
https://github.com/ctfs