ip echo - Show request headers and source IP of your request, similar to ipchicken.com
Hashes - Hash to SHA1/256/512, Md5 and more locally in JS without server connection
Base64 - Encode/Decode Base64 in your browser locally in JS (supports Unicode and UTF8)
Prettyprint JSON - Prints out JSON in a pretty,colored format
verify lua - Tells you lua syntax errors and, if none found, minifies your code
JWT Print - Prints out a JWT token in a readable manner
ASCII Codes - Cheatsheet about ASCII (no extended)
Contrast ratio - Calculate contrast ratio of 2 colors for readability purposes
List of colors - Color list with CSS names
RFC Searcher(external) - Search for RFCs with keywords