Base64URL Safe Encoder & Decoder
Convert between standard Base64 and URL-safe Base64URL (- instead of +, _ instead of /, no = padding). Standard for JWT tokens and web URLs.
1 How to Use Base64URL Safe Encoder & Decoder
- 1. Enter string.
- 2. Convert instantly with URL-safe substitutions.
- 3. Copy output.
⚙️ Cryptographic Specifications
- Algorithm
- RFC 4648 Base64URL
- Execution Engine
- Web Cryptography API (SubtleCrypto)
- Environment
- Client Browser Sandbox
- Network Telemetry
- 0 Bytes (Zero Server Transmission)
🛡️ Security & Compliance
Enterprise developers can safely execute this tool with production secrets. Because execution takes place entirely within your browser's local V8 JavaScript runtime, no payloads are transmitted over HTTP, cached on third-party proxies, or stored in server logs.
Verified Safe for SOC2, HIPAA, and GDPR developer compliance audits.
Frequently Asked Questions
What is the difference between Base64 and Base64URL?
Base64URL replaces + with - and / with _, and omits trailing = padding characters so it can safely appear in URLs and HTTP query parameters.
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