20 character password generator
Made on your device. Never sent or stored.
A random 20 character password, generated on your device. Change the character types below; the length stays at 20 unless you move it.
Is 20 characters long enough?
Twenty characters with all types gives about 129 bits, more than a 128 bit encryption key.
When to use it: For email, banking, password manager recovery codes stored offline, and administrator accounts.
How strong is a 20 character password?
A random 20 character password from letters and digits has 119.1 bits of entropy. With symbols added it has 128.9. Here is how that translates into guessing time for each character set.
| Characters | Pool | Bits | Fast hash | Slow hash |
|---|---|---|---|---|
| Digits only | 10 | 66.4 | 158 years | 158 million years |
| Lowercase letters | 26 | 94.0 | 32 billion years | 32 quadrillion years |
| Letters, both cases | 52 | 114.0 | 33 quadrillion years | over 1022 years |
| Letters and digits | 62 | 119.1 | 1 quintillion years | over 1024 years |
| All four types (this site) | 87 | 128.9 | 978 quintillion years | over 1026 years |
These figures only hold for random passwords like the ones above. A 20 character password you made up, with words, names or dates, is guessed far sooner. Test one with the strength checker.
Questions
How many combinations does a 20 character password have?
With the 87 characters used here, 87 to the power 20, about 1038. With letters and digits only, 62 to the power 20, about 1035.
Is this password stored anywhere?
No. It is generated in your browser with the Web Crypto API and never sent to a server.
Sources
- SP 800-63B-4, section 3.1.1.2: Password Verifiers, National Institute of Standards and Technology. Checked 18 October 2026.