How do I decode a JWT token?

JWT tokens have three Base64URL-encoded parts separated by dots. Paste the middle part (payload) into this decoder to see the claims. The header (first part) can also be decoded here.

Why won't my URL Base64 decode with regular decoders?

Regular Base64 decoders expect + and / characters, but URL-safe Base64 uses - and _ instead. Our URL-safe decoder handles these automatically, plus it restores any missing padding.

What's the difference between Base64 and Base64URL?

Base64URL replaces + with - and / with _ to make strings URL-safe without encoding. It also typically omits the = padding. Otherwise, the encoding algorithm is identical.

Can I decode standard Base64 with this tool?

Yes, but it's better to use our standard Base64 decoder for regular Base64. This tool is optimized for URL-safe variants and may process standard Base64 differently.

URL-Safe Base64 Decoder

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

Base64 Input

Decoded Text

Handles URL-safe characters (- and _)

Automatic padding restoration

JWT payload decoder

Error detection for invalid input

Related Base64 Tools

Base64 Encoder

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URL-Safe Encoder

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

Base64 Decoder

Decode any Base64 string back to original text instantly. Perfect for debugging APIs and decoding encoded data.

Image to Base64

Convert any image to Base64 data URI format. Perfect for embedding images in HTML, CSS, and JSON without external files.

How to Use the URL-Safe Decoder

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

1.Paste Base64 string in the input area
2.Click "Decode" to convert back to readable text
3.Copy the result or swap input/output
4.Check for errors if decoding fails

Common Use Cases

•Decoding JWT token parts
•Reading URL parameters
•Debugging API responses
•Extracting encoded filenames

Why Use Our URL-Safe Decoder?

•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.