Base64 Decoder
Paste a Base64 string and get readable text back — UTF-8 aware, forgiving of URL-safe alphabets and missing padding, with honest errors when it isn't text.
Decode text
Nothing leaves your deviceDecoded output
How to use this decoder
- Paste your Base64 string. Whitespace and line breaks inside it are ignored, so wrapped output works too.
- Read the result. Valid UTF-8 text shows instantly; the status line reports input characters versus decoded bytes.
- Handle odd input gracefully. URL-safe characters (-_) are converted back automatically, and invalid strings produce a clear error instead of mojibake.
- Copy the output with one click — or reverse the process with the Base64 Encoder.
Useful information
Decoding is the reverse of encoding: every 4 Base64 characters carry 3 bytes of data. This tool strips whitespace, repairs the URL-safe alphabet, restores missing padding, then interprets the bytes as UTF-8.
When the result isn't text
Not every Base64 payload is prose — images, ZIP files and compressed data often travel as Base64. If the bytes aren't valid UTF-8, the tool says so and reports the size rather than dumping unreadable noise at you. That's a signal you need a binary decoder, not this one.
URL-safe and missing padding
Tokens, JWTs and URL fragments often use -_ and drop the trailing = padding. Both are handled automatically — paste exactly what you received.
Common sources of bad input
Most failures come from truncation (an API cut the string short), accidental extra characters (quotes or a data: prefix), or double-encoding. If it fails, try trimming the string back to pure Base64 characters.
Frequently asked questions
How do I decode a Base64 string?
Paste the Base64 into the box — the decoded text appears instantly. Spaces and line breaks in the input are ignored, and URL-safe strings (-_) are handled automatically.
Why does my decoded text look like garbage?
Either the input wasn't Base64, or it encodes binary data (an image, a compressed file) rather than text. This tool reports the byte count when the result isn't valid UTF-8 text.
Does it support emoji and other languages?
Yes. Decoded bytes are interpreted as UTF-8, so emoji, Hindi, Arabic and other Unicode content come back exactly as they went in.
What if my Base64 uses - and _ instead of + and /?
No problem — URL-safe Base64 is converted back to the standard alphabet automatically, missing padding included.
Is my input stored anywhere?
No. Decoding happens entirely in your browser — the string is never sent to a server or saved by Jivora.