Base64 Encoder / Decoder

The Base64 Encoder / Decoder converts text into Base64 and back again, right in your browser. Base64 turns binary or UTF-8 data into an ASCII string, which is how images, tokens, and files travel inside text-only channels like JSON, email, or data URLs. Use it to inspect an encoded value, recover the original text, or produce an encoded string for embedding. Remember that Base64 is an encoding, not encryption: anyone with the string can decode it, so never rely on it to protect secrets. The tool runs entirely locally, so your input is never uploaded. Base64 exists because many channels are designed for text and will corrupt raw bytes, so binary data is mapped onto a safe alphabet of letters, digits, and two extra symbols with padding to square off the length. That is why images, certificates, and keys appear inside JSON as long strings, and why an attachment travels through email without damage. Seeing an encoded value and wanting to know what is inside it is the most common reason to decode, and producing one for embedding is the most common reason to encode. The expansion costs roughly a third more characters than the raw input, which is worth remembering when you are deciding whether to embed a file directly or serve it as a separate resource. Two cautions matter here: the encoding is not a security measure, since anyone who has the string can reverse it, and it is not compression, so it will always make the payload larger. The tool works entirely in the browser, so a token or a key you paste never leaves your machine.

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