What Is Base64 Encoding? (+ Free Encoder/Decoder)

Base64 is a way of encoding binary data — images, files, bytes — as plain text using 64 safe characters (A–Z, a–z, 0–9, + and /). It's not encryption; it's a reversible format that lets binary data travel safely through systems built for text, like email and JSON. Here's what it's for and how to encode or decode free with the Base64 Encoder.

What Base64 is for

Some channels only handle text reliably. Base64 turns any binary into a text string that survives them, then decodes back to the exact original. Common uses: embedding a small image directly in HTML/CSS, attaching files in email (MIME), and putting binary in JSON or a URL.

Encode and decode free

Paste a string into the Base64 Encoder to convert it either way — all in your browser, nothing uploaded. To turn an image into a Base64 data URI for inlining in code, use Image to Base64.

Important: it's not security

Base64 is encoding, not encryption — anyone can decode it instantly. Never use it to hide passwords or sensitive data. For integrity checks, use a hash instead — see the Hash Generator.

A size trade-off

Base64 makes data about 33% larger (it represents 3 bytes with 4 characters). That's fine for small assets but wasteful for big files — which is why you inline tiny icons but link to large images.

Bottom line

Base64 encodes binary as text so it can travel through text-only systems — reversible, not secure. Encode or decode free with the Base64 Encoder.