Base64 Encode / Decode

Base64 is a way of representing binary or text data using only 64 printable ASCII characters (A–Z, a–z, 0–9, + and /). It is used to safely transmit data through systems that only handle text, such as email attachments, data URLs, JSON, and HTTP basic authentication. It is an encoding, not encryption — anyone can decode it.

No. Base64 is reversible encoding with no secret key, so it provides no security or privacy — anyone can decode it instantly. It is only used to make data safe to store or transmit as plain text. Never use Base64 to protect passwords or sensitive information; use real encryption for that.

Base64 represents every 3 bytes of input as 4 characters of output, so encoded data is about 33% larger than the original. Padding with = signs may add one or two more characters. This size increase is the trade-off for making arbitrary data safe to transmit as text.

Yes. This calculator encodes text as UTF-8 before converting to Base64, so accents, emoji, and non-Latin scripts (Arabic, Chinese, Cyrillic, and more) all round-trip correctly. Decoding reverses the process to give you back the exact original text.

They are padding. Base64 works in blocks of 4 characters representing 3 bytes. When the input length is not a multiple of 3, one or two = characters are added so the output length stays a multiple of 4. The padding is required for the data to decode correctly.