What is Base64?
Base64 is a binary-to-text encoding scheme that converts binary data into a sequence of printable ASCII characters. It uses a 64-character alphabet — uppercase letters (A–Z), lowercase letters (a–z), digits (0–9), and two additional symbols (+ and /) — to represent every 6 bits of input as one character. This makes it safe to transmit binary data through text-only channels like email, JSON, URLs, and HTML attributes.
How to Encode and Decode Base64
To encode, paste your text into the input field on the left — the Base64 output appears instantly on the right. To decode, switch to decode mode and paste your Base64 string. Our tool handles UTF-8 characters (emojis, accented letters, CJK) correctly by encoding the UTF-8 byte sequence, not just the ASCII characters.
What is URL-safe Base64?
Standard Base64 uses + and / characters, which have special meanings in URLs. URL-safe Base64 replaces + with - and / with _, making the output safe to embed in URLs, filenames, and query parameters without encoding. Toggle the "URL-safe" checkbox to use this variant.
Is My Data Safe?
Yes. All encoding and decoding happens entirely in your browser using JavaScript. No data is ever sent to a server, stored, or logged. You can even use this tool offline once the page has loaded.