Free Online Converters
Free online converters that turn one thing into another in seconds — temperatures, encoded text, and more. Each one runs instantly in your browser, with no sign-up and nothing stored. Pick a converter below to get started.
Celsius to Fahrenheit
Convert temperatures between Celsius, Fahrenheit and Kelvin instantly, with the formula shown.
Convert NowBase64 Encoder & Decoder
Convert text and files to Base64 and back — encode or decode instantly, with URL-safe mode.
Encode / DecodeUnit Converter
Convert length, weight, temperature, volume and speed between metric and imperial units instantly.
Convert UnitsNumber to Words
Spell any number in English, or write amounts for cheques and invoices with currency mode.
Convert NowRoman Numeral Converter
Convert numbers to Roman numerals and back, with built-in validation. Covers 1 to 3999.
Convert NowData Storage Converter
Convert bytes, KB, MB, GB, TB and PB in both decimal and binary units, with a full breakdown.
Convert Now