🔐 What is Base64 Encoding?
Base64 is an encoding scheme that converts binary data into 64 ASCII characters (A-Z, a-z, 0-9, +, /). It is widely used in email systems (MIME), HTML Data URLs, REST API communication, and anywhere binary data needs to be safely transmitted through text-only channels. While it increases data size by roughly 33%, it ensures data integrity across different systems.
📋 Common Use Cases
Email Attachments
MIME standard encodes attachments in Base64 because email protocols only support 7-bit ASCII.
Data URLs (Inline Images)
Embed images directly in CSS or HTML using data:image/png;base64,... format.
JWT Tokens
JSON Web Token Header and Payload are encoded using Base64url encoding.
API Authentication
HTTP Basic Auth sends username:password encoded in Base64.
Frequently Asked Questions
Is Base64 encryption?▼
No, Base64 is encoding, not encryption. Anyone can easily decode it, so never use Base64 alone to protect passwords or sensitive information.
How much larger does Base64 make data?▼
Base64 increases data size by approximately 33%. This is because 3 bytes of original data are converted into 4 Base64 characters.
What is the difference between Base64 and Base64url?▼
Base64url replaces + with - and / with _, and omits padding (=) to make it URL-safe. It is commonly used in JWT tokens.