Base64 Encode / Decode

About the Base64 Encoder / Decoder

Base64 turns any data — text, images, fonts, binaries — into a plain-text string made of letters, digits, and a couple of symbols. That makes it safe to drop into places that only accept text: JSON payloads, data URIs in CSS or HTML, JWTs, email attachments, API keys, and config files. This tool encodes and decodes it instantly, both directions, for text and files, without sending anything to a server.

Because it runs entirely in your browser, you can safely encode or decode sensitive values — tokens, credentials, private keys — without pasting them into a site that logs what you submit.

What it handles

• Text ⇄ Base64, fully UTF-8 safe — emoji, accents, and non-Latin scripts encode and decode correctly (plain btoa can't do this on its own).
• Files → Base64 — encode an image, PDF, or any file to a Base64 string or a ready-to-paste data: URI.
• Base64 → file — paste a Base64 string (or a full data URI) and download the original file back, with the type detected from the URI when present.
• URL-safe variant — swap +/ for -_ and drop padding, the form used in URLs, JWTs, and filenames.
• Data URI output — wrap the result as data:<mime>;base64,… for inlining directly into HTML or CSS.

Tips

• Hit Swap to send the output back into the input and flip between encode and decode — handy for round-tripping a value.
• Decoding accepts both standard and URL-safe Base64, with or without padding, and ignores stray whitespace and line breaks.
• If a decode fails, the string usually isn't valid Base64 — check for truncation or stray characters; the tool will tell you.
• Base64 makes data about 33% larger. It's for safe transport, not compression.

No account, no upload — encode, decode, copy or download.

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