Base64 Decoder Online
Online Base64 decoder: paste a Base64 string and restore the original text or bytes, with automatic UTF-8 detection — handy for checking API responses and config.
Decoding is the inverse of encoding: it turns a Base64 string back into the original bytes or text. If the original content was UTF-8 text (for example Chinese), the tool automatically restores it as readable characters.
If you see a "not a valid Base64 string" message, it is usually caused by extra spaces, line breaks, or non-Base64 characters such as quotes or escape sequences. Clean the input and try again.
Decoding is commonly used to inspect encoded fields returned by an API, read encoded values in config files, or restore a Base64 snippet a colleague sent you.