A Practical Guide to the Bcrypt Hashing Algorithm

Learn how the bcrypt hashing algorithm protects passwords, why salt rounds matter, and how to implement bcrypt in Node.js with real examples. Our 24/7 Live Support Team is always here to help you.

Data breaches don’t happen because systems stop working. They happen because someone left the door unlocked. In most cases, that door is weak password storage. Plain-text passwords are still one of the biggest mistakes businesses make, and the cost of fixing that mistake often runs into millions.

That’s where the bcrypt hashing algorithm earns its place.

Passwords should never be stored in a readable format. Instead, they must be transformed into hashes that cannot be reversed. Unlike basic hashing methods, bcrypt was built with one clear goal: stay strong even as computers get faster. As a result, it has become the industry standard for password security.

Why the Bcrypt Hashing Algorithm Still Matters

Technology keeps evolving. Hardware gets faster. Attackers get smarter. However, many older hashing algorithms fail to scale with this growth. They run too fast, which makes brute-force attacks easier over time.

The bcrypt hashing algorithm solves this problem using a configurable work factor, also known as salt rounds. Simply put, you can slow the hashing process down on purpose. Therefore, even if an attacker has powerful hardware, cracking passwords becomes expensive and time-consuming.

Moreover, bcrypt automatically handles salting. This means even identical passwords produce different hashes, which blocks rainbow table attacks entirely.

Bcrypt in Action: Salt Rounds vs Hashing Time

To see how salt rounds affect performance, here’s a real Node.js example. As the rounds increase, hashing time increases as well, exactly what we want for security.

Install bcrypt

npm install bcrypt

Test hashing time with different salt rounds

const bcrypt = require("bcrypt");

const plainText = "EDYu9943^%*_79";

for (let rounds = 9; rounds <= 15; rounds++) {

console.time(`cost = ${rounds}, hashing time`);

bcrypt.hashSync(plainText, rounds);

console.timeEnd(`cost = ${rounds}, hashing time`);

}

Sample Output

cost = 9, hashing time = 65.683 ms

cost = 10, hashing time = 129.227 ms

cost = 11, hashing time = 254.624 ms

cost = 12, hashing time = 511.969 ms

cost = 13, hashing time = 1015.073 ms

cost = 14, hashing time = 2043.034 ms

cost = 15, hashing time = 4088.721 ms

As shown above, every extra round roughly doubles the time. Consequently, attackers face the same slowdown.

Implementing the Bcrypt Hashing Algorithm in Node.js

Here’s how to generate a salt and hash a password using bcrypt.

const bcrypt = require("bcrypt");

const saltRounds = 10;

const plainText = "EDYu9943^%*_79";

bcrypt

.genSalt(saltRounds)

.then(salt => {

console.log(`salt = ${salt}`);

return bcrypt.hash(plainText, salt);

})

.then(hash => {

console.log(`hash = ${hash}`);

})

.catch(err => console.error(err.message));

At this stage, the password is safely transformed into a hash that cannot be reversed.

Validating Passwords the Right Way

When a user logs in, you never decrypt anything. Instead, you compare the entered password with the stored hash.

const bcrypt = require("bcrypt");

const hash = "$2b$10$//DXiVVE59p7G5k/4Klx/ezF7BI42QZKmoOD0NDvUuqxRE5bFFB";

const plainText = "EDYu9943^%*_79";

bcrypt

.compare(plainText, hash)

.then(result => {

console.log("result =", result);

})

.catch(err => console.error("error =", err.message));

If the result is true, access is granted. Otherwise, it’s denied.

Conclusion

The bcrypt hashing algorithm isn’t trendy, it’s trusted. It scales with hardware, slows attackers down, and protects users even after a breach. For any application that handles logins, bcrypt isn’t optional anymore. It’s the baseline.