Base64 Encode / Decode

What is Base64?

Base64 encodes binary or text data using 64 ASCII characters, so it can travel safely through systems that only handle text — email, JSON, data URLs, and HTTP headers. It isn't encryption: anyone can decode it. Use it for transport, not secrecy.

Where you'll encounter it

• Email attachments: the MIME standard Base64-encodes files so they survive text-only mail systems.
• Data URLs: small images embedded directly in HTML/CSS as data:image/png;base64,....
• API tokens & config: binary keys and credentials are often stored as Base64 text.
• JWTs: JSON Web Tokens are made of Base64url-encoded segments.

Important: it's encoding, not encryption

Base64 is completely reversible by anyone — it hides nothing. Never use it to protect passwords or secrets; use real encryption for that. Its only job is to package data as safe, printable text. Note also that Base64 makes data about 33% larger, since it uses four characters for every three bytes, so it's for compatibility, not compression. For a fuller explanation, see our guide on what Base64 encoding is.

Full UTF-8 support, fully private

This tool correctly handles Unicode text — emoji, accents, non-Latin scripts — in both directions, and runs entirely in your browser. Nothing you encode or decode is ever uploaded, so it's safe for sensitive strings and works offline.