Input
Max 2 MB. Base64 encode only.
Result
Method—
Input0
Output0
How this Base64 and URL encoder works
Encode turns text or a file into Base64, or a URL into a safe string. Decode reverses it, including data URIs. Everything runs in the browser.
URL-safe Base64 replaces + and / with - and _ and drops padding. That is how JWT header and payload look. Query-value encoding encodes everything; full-address encoding keeps : / ? #.
Base64
Text or file
Standard, URL-safe (JWT) or a data URI from a file.
URL
Text ↔ %20
Query value (everything encoded) or full address (scheme kept).
Reverse
Encode and decode
Both directions work. Swap moves the result back into the input.
Important:
Base64 is not encryption. Anyone can decode the text. Do not paste secrets you want to keep private.
Useful notes
- “Hello, world!” in Base64 is SGVsbG8sIHdvcmxkIQ==. The decode sample uses it.
- URL-safe Base64 is the JWT form: no =, and - _ instead of + /.
- Query-value encoding turns a space into %20 and decodes + as a space. Full-address encoding leaves https:// and / alone.
- A data URI (data:image/png;base64,…) is decoded automatically. Binary files are downloaded, not shown as text.
- Nothing is saved on the server. Reloading the page clears the fields.