Base64 Encoder

Real-World Developer Scenarios

1. Embedding a Small Logo in CSS

.logo {
  background-image: url('data:image/svg+xml;base64,PHN2ZyB4bWxucy...');
}

This eliminates one HTTP request for the logo asset. Only use this approach for small images (under 5KB) — for larger images, the size overhead and lack of caching make external files preferable.

2. Inspecting a JWT Token

JWT tokens consist of three Base64URL-encoded sections separated by dots. To read a JWT's header or payload, split on the dots and decode each section. Flixfer's encoder/decoder makes this trivial for debugging authentication issues.

3. Basic Auth Headers

HTTP Basic Authentication requires credentials to be encoded as Base64(username:password) in the Authorization header:

Authorization: Basic dXNlcm5hbWU6cGFzc3dvcmQ=

Common Pitfalls

• Don't use Base64 for passwords — Base64 is trivially decoded. Always hash passwords with bcrypt, Argon2, or similar.
• Watch for padding issues — Base64 strings must have a length divisible by 4. Missing = padding characters can cause decoding failures.
• Newlines in output — Some tools insert newlines every 76 characters (MIME standard). If you're embedding in a URL, ensure newlines are stripped.