Base64 is Not Encryption: Security Misconceptions Explained

Table of Contents

• The Core Misconception
• How Trivial Decoding Is
• Real-World Mistakes
• What To Use Instead

The Core Misconception

Base64 looks like this: SGVsbG8sIFdvcmxkIQ==

It's unreadable at a glance, so developers sometimes treat it as a form of security. It is not. Base64 is reversible encoding with no key, no secret, and no security whatsoever.

How Trivial Decoding Is

atob("SGVsbG8sIFdvcmxkIQ==") // "Hello, World!"

One browser console command. Any developer — or attacker — can decode it in seconds.

Real-World Mistakes

Storing passwords as Base64

user: admin
password: YWRtaW4xMjM=  <- This is just "admin123"

"Hiding" API keys in frontend code

const key = atob("c2stbGl2ZV9zZWNyZXRfa2V5XzEyMw==");
// Anyone can open DevTools and see this

What To Use Instead

Base64 is encoding, not encryption. Use it for format compatibility, not security.