Convert text to hexadecimal and the other way for any string input.
Make sure your passwords are good enough.
Generate deep link mailto with subject, body, cc, bcc & get the HTML code as well.
Validate JSON content and make it looks good.
Easily generate dummy text with the Lorem Ipsum generator.
Upload a QR code image and extract the data out of it.
Easily convert IDN to Punnycode and back.