What is URL-safe Base64?

URL-safe Base64 (also called Base64URL) replaces + with - and / with _ to avoid issues in URLs. Standard Base64's + and / have special meanings in URLs and would need percent-encoding.

When should I use URL-safe Base64?

Use URL-safe Base64 when your encoded data will appear in URLs, query strings, filenames, or anywhere that + and / characters could cause problems. JWT tokens use URL-safe Base64.

Is URL-safe Base64 compatible with standard Base64?

They're interchangeable with simple character replacement. Our decoder handles both automatically. The only difference is the two characters: + becomes - and / becomes _.

Does URL-safe Base64 have padding?

URL-safe Base64 typically omits the = padding characters since they also need encoding in URLs. Our encoder removes padding by default, and our decoder handles strings with or without padding.

URL-Safe Base64 Encoder

Encode text to URL-safe Base64 format. Replaces + with - and / with _ for safe use in URLs and filenames.

Text Input

Base64 Output

URL-safe character set (- and _ instead of + and /)

No padding characters needed

Perfect for JWT tokens

Safe for filenames and URLs

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Decode URL-safe Base64 strings back to original text. Handles - and _ characters and missing padding automatically.

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How to Use the URL-Safe Encoder

Our url-safe encoder makes Base64 encoding and decoding simple:

1.Enter your text in the input area on the left
2.Click "Encode" to convert your text to Base64
3.Copy the result with one click to use anywhere
4.Use "Swap" to quickly decode the result back

Common Use Cases

•Creating JWT tokens
•Encoding URL parameters
•Safe filename generation
•Cookie value encoding

Why Use Our URL-Safe Encoder?

•100% Private: All processing happens in your browser
•No Registration: Use immediately without creating an account
•No Limits: Process as much data as you need
•Works Offline: Once loaded, works without internet
•Unicode Support: Full emoji and international character support

Technical Details

Base64 encoding uses a 64-character alphabet to represent binary data as ASCII text. Every 3 bytes of input become 4 characters of output (~33% size increase).

Our tool uses the browser's native btoa() and atob() functions for fast, reliable conversion. Unicode text is first converted to UTF-8.

About URL-Safe Base64

URL-safe Base64 (Base64URL) uses URL and filename-safe characters:

•+ becomes - (hyphen)
•/ becomes _ (underscore)
•Padding = is typically omitted

Required for JWT tokens, URL parameters, and filenames.