All the following tools run 100% client-side. That’s pretty much the whole point of it: no server computation = cheap for me and privacy for you. Win-win ;)

• Convert JSON to string and string to JSON
• Convert UTF-8 text to and from hexadecimal
• Convert UTF-8 text to and from base64
• Compute various text hashes (MD5, SHA-256, SHA-512, etc)
• Convert timestamp to UTC date and UTC date to timestamp
• Energy needed to heat water
• Energy needed to lift a mass
• French RIB key calculator
• Loan interests calculator
• Minify or beautify JSON
• QR code generator
• Steam booster pack creator list extractor
• Random file generator
• Random string generator
• Roman to alternative, look-alike characters
• URL decoder / encoder