Base64 to Text Converter: Decode Base64 Back to Readable Text

What the conversion actually does

Base64 packs every 3 bytes into 4 printable characters drawn from A-Z, a-z, 0-9, + and /. Decoding unpacks those 4 characters back into the original 3 bytes exactly — the process is lossless.

Turning bytes into text is a second, separate step. The decoder assumes UTF-8, which is right for nearly everything on the modern web. If the original bytes were Latin-1 or UTF-16, you will see replacement characters even though the Base64 decode itself succeeded.

Four reasons decoded text looks wrong

Wrong padding. Valid Base64 has a length divisible by 4, padded with one or two "=" at the end. A string copied out of JSON or a log line often loses its padding; adding it back fixes the decode.

Base64url instead of standard Base64. JWTs and URL-safe payloads use "-" and "_" in place of "+" and "/", and usually drop padding entirely. Swap those two characters back before decoding.

Line breaks and whitespace. MIME-style Base64 wraps at 76 characters. Most decoders tolerate the newlines, but a stray space in the middle of the string will not decode.

It was never text. If the Base64 encodes a PNG, a PDF or a gzip stream, decoding to text gives binary noise. Check the first decoded bytes — a file signature like PK or %PDF tells you what you actually have.

Reading the output safely

Base64 is encoding, not encryption. Anything encoded is trivially readable by anyone who has the string, so treat a Base64 blob in a log or a URL as plaintext for security purposes.

Our converter runs entirely in the browser, which matters when the payload is a token or a customer record — those should not be pasted into a server-side decoder you do not control.