How Hackers Crack Passwords: Brute Force, Dictionary and Rainbow Tables
Attackers rarely guess one password at a time by hand. They use software that tests billions of combinations. Knowing the methods explains what makes a password strong.
Brute force
The attacker tries every possible combination. Time grows quickly with each additional character, so long passwords become impractical to crack.
Dictionary attacks
Software tries common words, names and known passwords from past breaches, often with predictable changes such as adding numbers or swapping letters.
Credential stuffing
Leaked username and password pairs are tried on other sites. This is why password reuse is dangerous.
Rainbow tables and hash cracking
If a site stores passwords poorly, attackers who steal the database can try to match the stored hashes against precomputed lists. Modern sites use salting and slow hashing to prevent this.
What this means for you
- Use long passphrases or random passwords.
- Never reuse passwords.
- Avoid common patterns and personal details.
- Add two-factor authentication.
