Base64 Encoder & Decoder
Convert plain text to Base64 or decode a Base64 string back to readable text, with full Unicode support and one-click copy.
Result appears here.100% private
This tool runs entirely in your browser. Nothing you type is uploaded, logged or stored.
Base64 Encoding in Web Development
Base64 encodes binary data using 64 printable ASCII characters so it can travel safely through channels that expect text: JSON bodies, HTTP headers, email attachments, data URIs and JWT segments. Every three bytes become four characters, so encoded output is roughly 33% larger than the source.
Common uses include inlining small images or fonts as data URIs to avoid an extra request, transmitting binary payloads inside JSON APIs, and encoding Basic Authentication credentials in the Authorization header. Note the last one carefully: Base64 is an encoding, not encryption. Anyone can decode it instantly, so it provides zero confidentiality — always pair it with TLS and never use it to “hide” secrets.
For URLs, use the URL-safe variant that replaces + and / with - and _, otherwise your string may break when parsed as a query parameter.
Frequently asked questions
No. It is a reversible encoding with no key. Anyone can decode a Base64 string, so never use it to protect passwords or private data.