Overview

Base64 Course

Learn Base64 encoding from first principles: binary-to-text, padding, URLs, and common pitfalls.

This course teaches Base64 as an encoding subject—how binary data becomes printable ASCII text, why padding appears, and where developers meet it in the wild. It is not a walkthrough of any single product or editor.

Who this course is for

  • Developers who copy Base64 strings without knowing what changed (or what can go wrong)
  • Backend and frontend engineers working with tokens, images, and URL-friendly payloads
  • Anyone comparing Base64 to hex or debugging “invalid character” decode errors

What you will learn

  1. What Base64 is for and typical places you see it
  2. The bit-level idea: groups of six bits and a 64-character alphabet
  3. Padding (=), output length, and how it ties to input byte count
  4. Standard Base64 vs URL-safe variants and data: URIs
  5. When Base64 wins or loses against hexadecimal encoding
  6. Frequent mistakes: wrong alphabet, line breaks, and UTF-8 confusion

How to use this course

Use the table of contents on the left to move between lessons. The sequence is designed to build intuition before syntax details and edge cases.

If you want to experiment after a lesson, you can use the related Base64 tool—but the goal here is understanding the encoding, not memorizing UI steps.

Start lesson 1