RandomNr

Random Lock Combination Generator

Generate combinations for dial and digit locks, in the length and range your lock uses.

Random Lock Combination Generator

24-8-31

Dial combination 0 to 39

How many combinations

Lock type

How to use the lock combination generator

  1. Choose a 3 number dial in the 0 to 39 style, or a 3 or 4 digit keypad code.
  2. Generate one combination or a batch for many lockers.
  3. Copy or export the combinations, then set them on your locks.

What is a lock combination generator

A lock combination generator produces combinations for dial and digit locks, in the length and range your lock actually uses. Set how many numbers the combination has and the range each can take, and Random Nr draws a fresh combination, which is a quick way to set a new code for a padlock, a safe or a locker.

How many combinations each lock has

The keyspace of a lock is simply how many settings its dial or keypad allows, and it varies more than people expect.

Lock typeCombinationsKeyspace
3 digit keypad1,00010 to the 3
4 digit keypad10,00010 to the 4
Dial 0 to 39, three numbers64,00040 to the 3

A three number dial lock looks the strongest at 64,000 settings, and mathematically it is, which is why this tool never repeats a number back to back on the dial, a sequence that is easy to misdial.

Why combination locks are easy to crack

The 64,000 figure is the theoretical keyspace, not the practical one. A well known weakness in common dial padlocks lets the last number be found mechanically and the first two narrowed sharply, cutting the real search space to around 100 combinations. A random combination does not fix that hardware weakness, but it does defeat the far more common attack: someone simply trying a birthday, 1234, or the factory default. Randomness is the defence you control.

How to set and remember a combination

Generate a combination here, set it following the reset instructions for your lock, and store the number in a password manager rather than on a sticky note. Nothing generated on this page leaves your device. For a card or phone PIN rather than a lock, use the PIN code generator, which filters out the weak codes people reach for.

More code and ID generators

Frequently asked questions

What lock types are covered

A three number dial in the 0 to 39 range of a rotary padlock, and three or four digit codes for keypad and cable locks.

Why avoid repeats on the dial

On a dial, turning to the same number twice in a row can be missed, so the tool never repeats a number back to back.

Can I generate several

Yes, up to 500 at once, handy when setting many lockers, ready to copy or export.

Are the combinations random

Yes. Every number is drawn from the browser cryptographic random source, so combinations are hard to guess.

Is it free

Yes, free and with no sign up.

Related generators

For a card or phone code see the PIN code generator.