A random 8-character password using uppercase, lowercase, digits and 14 symbols has about 50 bits of entropy, or 48.9 bits with the "one of each type" rule on. That sounds large, yet four gaming GPUs working through a stolen NTLM hash would cover half of those passwords in roughly 4 minutes. NIST now accepts 8 characters only when a second factor backs the password up.
Where the number 8 came from
Eight characters became the default minimum decades ago, partly for technical reasons. The traditional Unix password hash, based on the DES cipher, only looked at the first 8 characters of whatever you typed and ignored the rest. Many later rules simply kept the number.
It is still everywhere. Wi-Fi WPA2 passphrases must be at least 8 characters. Microsoft Entra ID and the default AWS IAM password policy both start at 8. OWASP's verification standard for web apps (ASVS 5.0) puts its floor at 8 while "strongly" recommending 15. Microsoft's Group Policy reference for Windows still suggests 8 as a minimum, and the default domain policy is 7.
What has changed is the hardware on the other side. A single current gaming graphics card can test hundreds of billions of guesses per second against weak hash formats, which turns 8 characters from "good enough" into "good enough only with help".
Generate an 8-character password
- Leave the length at 8; uppercase, lowercase, digits and symbols are already on.
- Keep "at least one of each type" on if the site asks for mixed characters.
- Press Generate and read the entropy figure, about 49 bits.
- Copy it into the site and into your password manager.
- Turn on two-step verification for the account, because at this length the second factor is doing much of the work.
How long 8 random characters last
These are times to search half of all possible passwords, which is what an attacker needs on average. They assume the attacker knows exactly how the password was made and has a copy of its hash, so this is an offline attack. Three guess rates are used, each an assumption rather than a measurement of any particular attacker:
- 10⁴ per second, slow hash: a single RTX 4090 grinding bcrypt hashes stored at cost 10. Its benchmark showed 184,000 tries per second at cost 5; every extra cost step halves the speed, which lands near 5,750 per second.
- 10¹⁰ per second, fast hash: the same card against unsalted SHA-256, which it ran at about 22 billion per second.
- 10¹² per second, fast hash rig: four such cards against NTLM, the Windows hash, at about 288 billion each.
| 8 characters from | Bits | Slow hash, 10⁴/s | One fast GPU, 10¹⁰/s | GPU rig, 10¹²/s |
|---|---|---|---|---|
| Digits only | 26.6 | 1 hour | under a second | instant |
| Lowercase letters | 37.6 | 121 days | 10 seconds | under a second |
| Letters and digits | 47.6 | 346 years | 3 hours | 2 minutes |
| All four, one of each type | 48.9 | 837 years | 7 hours | 4 minutes |
| All four, any mix | 50.0 | 1,763 years | 15 hours | 9 minutes |
The rightmost column is the one to take seriously. Against NTLM, even one RTX 4090 would cover half of the "one of each type" space in about 15 minutes. The slow-hash column shows the other side: if the site stores passwords properly, the same 8 characters hold out for centuries. You usually cannot tell which kind of site you are dealing with.
A quirk of short passwords: the "one of each" rule costs a bit
At this length, mixing rules remove a surprising share of possibilities. Only 47.5% of random 8-character strings drawn from all 76 characters contain every type. The rest are missing at least one, usually digits or symbols, simply because each makes up a small part of the set. Requiring one of each therefore halves the number of possible passwords, a loss of about 1.1 bits. The generator's meter shows that conservative figure. It is a small cost, and many sites will not accept the password without it, but it is one more reason short passwords leave little margin.
What standards say about 8
- NIST SP 800-63B-4 (2025) allows 8 characters only when the password is used together with another authentication factor. Used alone, a password must be at least 15 characters. The previous revision (2017) had made 8 the general minimum for passwords users choose.
- PCI DSS 4.0, the payment card standard, raised its minimum to 12 characters from 31 March 2025. Eight is allowed only where a system cannot support 12. Before that date the requirement was 7.
- WPA2-Personal Wi-Fi accepts 8 to 63 characters, so 8 is the shortest network password a router will take.
Where 8 is acceptable
- An account with two-step verification or a passkey as backup, where the password alone cannot open it.
- A login that locks after a few failed tries and is never exposed to offline guessing, such as a device that enforces delays in hardware.
- A system that refuses anything longer. If you run into one, use all four character types so you get the full 50 bits, and ask whether the system can be configured to accept more.
Where 8 is not enough
- Anything that can be attacked offline: a Wi-Fi network, an encrypted file or archive, a password manager vault, a laptop disk.
- Accounts protected by the password alone. Use the 15-character preset to meet the NIST single-factor rule.
- Any password you reuse. A leak at one weak site exposes every account that shares it, at any length.
For Wi-Fi in particular, captured handshakes are tested offline with a deliberately slow key derivation, around 2.5 million guesses per second per RTX 4090. Half of the 8-character space would still fall to a hundred such cards in under two weeks. The Wi-Fi preset uses 20 characters instead.
Privacy
The 8 characters are drawn in this browser tab. They are not sent anywhere, not stored by the page, and not visible to anyone but you. When you leave the page, the result is discarded.
Technical note
Each character is chosen with crypto.getRandomValues and rejection sampling, so all 76 characters are equally likely and the entropy figure is exact. The methodology page explains how to check the absence of network requests yourself.
FAQ
Is an 8-character password safe?
Only with backup. With a second factor or strict attempt limits it is fine. As the only protection on something that can be attacked offline, it can fall in minutes to hours.
Why do so many sites still ask for just 8?
Old rules, user complaints and compatibility. Eight is easy to remember, and it matches older standards. The current NIST guidance treats it as a floor for multi-factor use, not a target.
Does adding a symbol make 8 characters strong?
Barely. Switching from letters plus digits to the full four-type set adds roughly 2.3 bits here. Adding two more characters adds about 12.5 bits, so length is the better lever.
Is an 8-digit PIN the same as an 8-character password?
No. Eight digits give 26.6 bits against about 50 for 8 mixed characters, which works out to roughly ten million times fewer possibilities. PINs depend entirely on attempt limits; see the PIN preset.
What is the shortest password worth generating here?
The tool goes down to 4 characters for systems that need it, but for an account password, start at 8 only if a second factor exists, and at 15 otherwise.
Sources
- NIST: SP 800-63B-4 authenticator rules
- NIST SP 800-63B (2017), section 5.1.1
- PCI DSS 4.0 questionnaire text, 8.3.6
- Microsoft Learn: Minimum password length policy
- crypt(5): traditional DES truncation
- hashcat 6.2.6 benchmark on an RTX 4090
- OWASP ASVS 5.0.0
Checked 2026-10-11.
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