Quick Base64 Decoding
Got a Base64 string from an API response, a JWT payload, or a log file? Paste it below and see the decoded text immediately. No buttons to click — the output updates in real time as you type or paste. The tool automatically strips whitespace and handles missing padding.
Code Examples
JavaScript:
atob(base64String) (ASCII only)Python:
base64.b64decode(b64_string).decode('utf-8')PHP:
base64_decode($base64_string)Java:
new String(Base64.getDecoder().decode(b64), UTF_8)Go:
base64.StdEncoding.DecodeString(b64)Handling Encoding Errors
If decoding fails, the most common causes are: URL-safe encoding — the string uses - and _ instead of + and / (toggle URL-safe mode); missing padding — some encoders strip trailing = characters (this tool adds them back automatically); or non-Base64 characters in the input. Whitespace and line breaks are always stripped before decoding.