How Safecracking Works

Try-out Combinations and Day Locks

The easiest way to open a safe is to know the combination. Though this seems painfully obvious, knowing the combination is the most common way safecrackers open safes. But are they really cracking the safe if they know the combination? In a manner of speaking, yes. Combination deduction is the first step a safecracker takes in trying to get into a safe.

All safes are shipped from the manufacturer with try-out combinations. Ideally a safe owner resets the try-out combination after purchasing the safe. This doesn't happen as often as you would think. Many safe owners simply buy the safe and use the try-out combination; making their safe easy prey for safecrackers. The try-out combinations for most safes are an industry standard and widely known by both locksmiths and safecrackers. If it means not having to use more complicated methods to get in the safe, the few seconds it takes to test some of the more common try-out combinations are well worth the safecracker's time.


Time is the number one enemy of a safecracker. With that in mind, finding the combination is another preferred method of cracking. In addition to try-out combinations, safecrackers may use some poking around or a little research to try and get or guess the number before breaking out the tools.

Surprisingly, many people write the combination down near the safe, if not on the safe itself. Simply searching the room the safe is in is likely to get the safecracker the numbers he needs. A lot of safe owners will either scribble the combination on a wall or write it on a nondescript note.

Numerous businesses keep their safes on what locksmiths call day lock. By dialing all the numbers of the combination, business users unlock the company safe. Then when closing it, they do not cancel out the combination. This means someone can open the safe by simply opening the door or, at the most, just entering the last number of the combination. If a safecracker is lucky enough to come across a safe that has been day-locked, then at the very worst he need only guess at the last number.

The professional safecracker is well researched in both the type of safe he is cracking and the type of person who is using it. But when deduction fails, the safecracker must dig in and attempt to defeat the safe or lock.

Let's take a look at how safecrackers do this.