What is Base64 encoding?
Base64 represents binary data as ASCII text using 64 printable characters (A-Z, a-z, 0-9, +, /). It's used whenever binary or arbitrary text needs to travel safely through text-only channels — embedding images in CSS/HTML, encoding credentials in HTTPAuthorization headers, or packing binary payloads into JSON.
Standard vs. URL-safe Base64
Standard Base64 uses + and /, which have special meaning in URLs and file paths. URL-safe Base64 (RFC 4648 §5) replaces them with - and _ and drops the trailing = padding — this is the variant used by JWTs, for example.
FAQ
Is Base64 encryption?
No. Base64 is an encoding, not an encryption — anyone can decode it instantly with no key. Never use it to hide sensitive data.