Base64 Decoder
Decode Base64 strings back to readable text. Handles UTF-8, URL-safe Base64 and missing padding. Free, instant and fully in-browser.
Input
Result
The result appears here as you type.
What this tool is for
Paste a Base64 string and read what is inside it: a JWT payload, an encoded config value, a data URI. Padding is repaired automatically and the URL-safe alphabet is accepted, so strings pulled out of URLs decode without hand editing.
How to use it
- Paste the Base64 string.
- Read the decoded text: it appears as you type.
- Copy the result or download it as a file.
Frequently asked questions
Why does my string fail to decode?
Usually stray characters: a quote, a newline in the middle of a token, or a truncated copy. Whitespace and missing padding are handled here, anything else means the string is not valid Base64.
Can I decode a JWT with this?
You can decode the header and payload sections, which are URL-safe Base64 separated by dots. Paste one section at a time. The signature is binary and will not read as text, and decoding never verifies a token.