Why Never Use Base64 for Passwords

When building applications, handling user passwords securely is one of the most critical responsibilities. A common beginner mistake is confusing encoding (like Base64 or URL encoding) with encryption or hashing.

The Misconception

Some developers might think, “If I turn the password into a random-looking string of characters, it’s safe, right?”

// DON'T DO THIS
const password = "mysecretpassword";
const encoded = btoa(password); 
console.log(encoded); // "bXlzZWNyZXRwYXNzd29yZA=="

This looks unreadable to a human, but it is not secure.

Encoding vs. Hashing

Base64 Encoding

Base64 is a binary-to-text encoding scheme. It is designed to transport data, not protect it. It is a two-way process. You can see this in action using our Base64 Encoder tool to instantly encode and decode any text.

• Public Algorithm: Everyone knows how Base64 works.
• Reversible: Anyone can decode it instantly without a key.

// Decoding is trivial
const decoded = atob("bXlzZWNyZXRwYXNzd29yZA==");
console.log(decoded); // "mysecretpassword"

If you store passwords as Base64 in your database, and your database leaks, every single user account is immediately compromised.

Hashing

Hashing is a one-way process. You transform the data into a fixed-size string of characters, which cannot be reversed to get the original data.

• One-way: You can’t turn the hash back into the password.
• Verification: To check a password, you hash the input and see if it helps matches the stored hash.

What to use instead?

Use industry-standard hashing algorithms designed for passwords, such as:

1. Argon2 (Recommended)
2. Bcrypt
3. Scrypt

These algorithms are “slow” by design, making it computationally expensive for attackers to guess passwords using brute-force attacks.

Summary

• Base64: Just a different representation of data. Zero security.
• Hashing: Mathematically irreversible transformation. Secure.

Never use Base64, raw MD5, or simple SHAs for password storage. proper libraries/tools that implement Argon2 or Bcrypt.