Developer

Small developer utilities that run in your browser: format JSON, encode Base64 and URLs, hash text, make UUIDs and convert timestamps, subnets and number bases. Nothing is sent anywhere.

Color Contrast CheckerWhether text is readable on a background.Developer

Subnet CalculatorNetwork, broadcast and usable hosts from an IPv4 CIDR.Developer

Unix Timestamp ConverterSeconds or milliseconds, and the UTC and local time.Developer

UUID GeneratorRandom UUID version 4 values. Nothing is stored.Developer

JSON FormatterIndent it, or point at the character that broke.Developer

Base64 Encode and DecodeText or a small file, turned into the safe character set.Developer

Color PickerOne colour as hex, RGB, HSL, and lighter or darker steps.Developer

Hash GeneratorSHA-256 in the browser, with SHA-1 only as an old checksum.Developer

URL EncoderEncode a space, & or ? so it does not break a link.Developer

Number Base ConverterDecimal, hex, binary and octal, side by side.Developer