Use the password manager’s suggested length for accounts you do not need to memorize. If a generator is available, choose a long random password rather than trying to invent one yourself. For most generated passwords, length matters more than adding special characters. In practice, 11 to 15 characters is strong enough for everyday use, and 20 characters is a safer default when the tool recommends it.
Choosing Length for Generated Passwords
When a password manager can generate and store credentials, length becomes the main lever because the tool removes the burden of memorisation. The practical choice is usually to let the manager generate a long random password instead of trying to make one memorable, because randomness and length together defeat guessing far better than human-made patterns.
For that reason, the right length is not a fixed “magic number” so much as a floor that matches the account’s value and the tool’s capabilities. For ordinary accounts, a generated password in the low teens is usually strong enough; for high-value accounts, or where the manager easily supports it, a longer generated password is the safer choice.
The important distinction is between generated secrets and human-created passwords. Human-chosen passwords are often shortened, patterned, or repeated across accounts, which makes them predictable even when they look complex. A long random password avoids that weakness, and once the manager stores it, usability no longer depends on keeping it in memory.
Why Length Beats Character Tricks for Managed Credentials
Password strength comes from the size of the search space an attacker would have to brute-force or guess. Adding a special character helps less than many people assume if the password is still short or if the surrounding pattern is predictable. A random 12-character password is typically far harder to attack than an 8-character password with symbols inserted in a human-friendly way.
This is why generated passwords should be treated differently from passwords made by a person. A manager can safely create a string that is awkward to type, because the user does not need to reproduce it manually. That shifts the optimisation from memorability to resistance against guessing, reuse, and credential stuffing.
In practice, length also helps compensate for future risk. Attack capability improves over time, and some services weaken the overall benefit of strong passwords through poor rate limiting or weak account recovery. A longer generated password gives more buffer against those conditions, even when other protections are imperfect.
For managed credentials, account recovery and password reset paths still matter. If the password is long but the reset channel is weak, the account remains exposed through the fallback process. That is why password length should be chosen together with MFA, recovery controls, and reuse avoidance rather than in isolation.
How to Set a Practical Default in Real Environments
A sensible policy is to standardise on the password manager’s suggested length unless there is a specific platform limit. Where teams need a simple default, 20 characters is a strong baseline for stored credentials because it gives wide margin without creating operational friction. If a target system rejects that length, use the longest accepted generated value and document the exception.
For shared organisational systems, the default should be consistent rather than personalised. Inconsistency invites bad habits, such as lowering length for convenience on some systems or keeping a short “temporary” password that never gets replaced. The manager should become the source of truth for the generated secret, not just a convenience tool.
When a password is not meant to be memorised, do not optimise for readability. Pronounceable strings, simple substitutions, and keyboard patterns all create structure that an attacker can exploit. The best practice is to use full random generation, maximum practical length, and unique values per account.
Teams also need to watch for application-specific limits. Some older platforms cap password length or mishandle certain characters, which can lead to silent truncation or unexpected login failures. If a system behaves badly with long generated passwords, that is a system constraint to document and remediate, not a reason to weaken the password policy everywhere else.
Risk and Threat Considerations
Long generated passwords reduce brute-force and credential-stuffing risk, but they do not solve weak recovery flows, reused credentials, or exposed password vault access. The main failure mode is not that the password is too long, but that teams treat length as a substitute for unique credentials, MFA, and secure storage.
Failure mechanism: Attackers usually win through password reuse, phishing, reset abuse, or stolen stored credentials rather than by guessing a single well-generated password. If the manager is compromised, the stored secret can be exposed regardless of length.
Impact: A long password still matters because it raises the cost of direct guessing and limits damage from service-side credential attacks, but the real security outcome depends on vault protection, account recovery hardening, and per-account uniqueness.
Standards & Framework Alignment
This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.
OWASP Non-Human Identity Top 10 addresses the attack and risk surface, while NIST SP 800-53 Rev 5 and OWASP ASVS set the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| OWASP Non-Human Identity Top 10 | NHI-02 — Secret Leakage | Managed passwords are secrets whose exposure is a primary risk here. |
| NHI-07 — Long-Lived Secrets | Stored passwords become long-lived credentials if not rotated or replaced. | |
| Recommendation — Use long unique generated secrets and protect vault access to reduce leakage impact. Set generated passwords with sufficient length and rotation discipline to limit secret longevity. | ||
| NIST SP 800-53 Rev 5 | IA-5 — Authenticator Management | Password length choice is part of authenticator lifecycle and strength management. |
| IA-2 — Identification and Authentication (Organizational Users) | User account authentication strength depends on the credential policy used. | |
| Recommendation — Configure authenticator issuance and storage to enforce strong generated credentials. Require strong generated passwords for accounts that rely on password authentication. | ||
| OWASP ASVS | V6 — Authentication | Generated password length is an authentication-strength decision for accounts. |
| Recommendation — Use strong generated passwords and avoid human-created password patterns. | ||
Practitioner Guidance
What to verify: Confirm the target system accepts the manager’s default generated length, preserves pasted values correctly, and does not truncate or reject long strings in hidden ways. If a system cannot handle the default, treat that as an application defect or exception case, not a reason to weaken your baseline.
Decision rule: If the account is stored in a password manager and does not need to be memorised, choose the longest random password the system reliably accepts, then keep it unique and non-reused. If the account is high-value, bias toward the higher end of the accepted range rather than the minimum.
Practitioner takeaway: Once a manager stores the secret, usability stops being the limiting factor, so the right policy is to maximise random length within system constraints and spend your control effort on uniqueness, recovery, and vault protection.
Related resources from NHI Mgmt Group
- How should security teams store high-value crypto seed phrases in a password manager?
- How should security teams choose between general-purpose hashing and password hashing for stored credentials?
- How should security teams evaluate the risk of putting sensitive credentials into a password manager or similar vaulting system?
- How should security teams authenticate AI agents in enterprise environments?
Deepen Your Knowledge
Reviewed and updated by the NHIMG editorial team on September 25, 2026.
NHI Mgmt Group — the #1 independent authority on Non-Human Identity, IAM, and Agentic AI security. nhimg.org
