SecurityNut password and credential generator for secure passwords, passphrases, PINs and API tokens

SecurityNut / Credentials
Generated locally with cryptographic randomness. Nothing leaves this device.
Web Crypto is not available in this browser, so generation is disabled. Please use a current browser.
Primary password · mpStyle Suitable for privileged accounts MP Approved
0 bits
For reading aloud. Capital letters are shown as capitalised words.
Strength Assessed against an RTX 4090-class GPU · 100 billion guesses per second
Estimated time to exhaust: —
Length 64
Three word passphraseNCSC style
0 bits
Digits 2 Symbol
PINNumeric code
0 bits
Digits 6
Wi-Fi passphraseEasy to read out
0 bits
Digits 2 Symbol set ! @ # $ % * + ?
Word and digitsLegacy complexity rules
0 bits
Digits 4
Diceware passphraseRandom word sequence
0 bits
Words 6
API tokenRaw key material
0 bits
Bytes 28
Split and recover · Shamir secret sharing
Divide a credential into shares. Any set meeting the threshold rebuilds it exactly; any smaller set reveals nothing at all.
Split
Shares 3 Required 2
Recover
Batch generation · For provisioning
Generate a set of credentials, one per line, using the current generator settings.
Style Count 10
Copied values include nothing else. Clear the set before leaving the machine unattended.
Shamir secret sharing

A secret is divided into a number of shares. Two values are chosen at the point of splitting: how many shares exist in total, and how many are required to rebuild the secret. The required number is called the threshold.

Any group holding at least the threshold can reconstruct the secret exactly. Any group below it learns nothing whatsoever. Not a partial hint, not a narrowed search space, nothing. This is a mathematical property of the scheme rather than a matter of computing power, so it holds no matter how capable an attacker may be.

Why it matters

Consider a vault. If one person holds the code, the code is unavailable whenever they are. If several people each hold the full code, every one of them is a point of compromise and each must be trusted completely. Splitting the code into shares resolves both problems at once: the vault opens only when enough authorised people act together, and no individual can open it alone.

If some shares are withheld, mistyped or deliberately false, and the correct shares presented fall below the threshold, the secret stays sealed.

Practical notes

Shares are generated on this device and never leave it. Store each share in a separate place, record the threshold somewhere sensible, and note that losing shares until fewer than the threshold remain makes the secret unrecoverable. That is the design working, not failing.