Encode and decode Base64URL format online
Text Tools
About This Tool
Base64URL Converter is an online tool that encodes text to URL-safe Base64 format and decodes Base64URL strings back to plain text. It replaces + with - and / with _, removes padding, and fully supports Unicode characters. All processing happens locally in your browser with no data sent to any server.
Key Features
- Bidirectional Base64URL encoding and decoding with URL-safe output
- Replaces + with - and / with _ for URL compatibility
- Removes padding = characters for compact output
- Full Unicode character support including CJK text
- One-click mode switching between encode and decode
- Built-in sample data to quickly test encoding and decoding
Use Cases
- Encode data for safe inclusion in URL parameters and query strings
- Decode JWT token payloads for authentication debugging
- Prepare Base64 data for OAuth 2.0 and OpenID Connect flows
- Encode binary data for JSON Web Signature and Encryption
- Convert standard Base64 to URL-safe format for web APIs
base64url
encoding
decoding
url-safe
Frequently Asked Questions
What is the Base64URL Converter?
Base64URL Converter is an online tool that encodes text to URL-safe Base64 format and decodes Base64URL strings back to text. It runs entirely in your browser with no data sent to any server.
What is the difference between Base64 and Base64URL?
Base64URL replaces + with - and / with _ to make the output URL-safe, and removes padding = characters. Standard Base64 contains characters that are problematic in URLs and query parameters, while Base64URL is designed specifically for web use.
Can I use this tool to decode JWT tokens?
Yes, JWT tokens use Base64URL encoding for their Header and Payload sections. You can paste the JWT payload portion into the tool in decode mode to reveal the JSON content inside.
Is my data safe when using the Base64URL Converter?
Absolutely. All encoding and decoding happens locally in your browser. No data is uploaded to any server, ensuring your information remains completely private and secure.
Can I use the Base64URL Converter on my phone?
Yes, the Base64URL Converter is fully responsive and works on all devices including smartphones, tablets, and desktop computers. On smaller screens the input and output panels stack vertically.