After a long day at work or a long night out, the last thing you'd want when you arrive home is to break your key inside of your door lock. It's a common problem that often prompts homeowners to call their locksmith, which could cost $35 to $250 according to recent CostHelper estimates. Before you pick up that phone, however, you'll want to try some of the tips and tricks mentioned below.

What You'll Need

First, you'll need to prepare the lock by spraying penetrating oil into the keyhole. This will lubricate the lock and allow the pins to move freely during the extraction process. Use a paper towel or an old rag to clean up the excess run-off.

Next, you'll need to make sure the tumbler is lined up properly so you can extract the broken key. Insert a flathead screwdriver into the edge of the tumbler and turn tumbler back to its default vertical position. You shouldn't use the remaining half of your broken key for this, since reinserting the rest of the key into the lock could push the broken half further into the lock.

Shallow Extraction

Shallow broken keys can be extracted using a small pair of needle-nosed pliers or tweezers. Carefully insert the tip of the pliers or tweezers into the keyhole and grip the broken key. Afterwards, carefully pull the broken key out of the lock. Make sure you don't accidentally push the key further into the lock.

Another viable option involves using super glue to extract the key from the lock. Place a small amount of super glue onto the end of a match or a thin, stiff wire. Hold the device against the edge of the key without pushing it further through the keyhole. Wait for as long as it takes for the super glue to harden and then carefully pull the key out of the lock.

You'll only want to use this method if the broken key is visible through the lock. If you use the super glue trick to extract a key that's deep within the lock, you could get it all over the lock tumblers, essentially freezing them in place and making the entire lock useless.

Deep Extraction

If the broken key is stuck deep within the lock, you may be able to use a small jigsaw or mini-hacksaw blade to extract the key. Insert the blade into the keyhole with the serrated edge pointing down. Use the serrated edge to hook and pull the key out of the lock.

You can also use two thin pieces of metal to slowly extract the broken key from the lock. Carefully insert a thin piece of metal on each side of the key. Apply pressure to both sides and carefully pull the key out of the lock. You may need to repeat this process multiple times before you successfully remove the broken key.

Last but not least, you can use a strong magnet to extract the broken key. However, you'll need the tumbler perfectly lined up. Otherwise, the key will just snag itself on the lock. This trick won't work on non-magnetic keys.

If all else fails, you may need a locksmith to extract the broken key for you. Your locksmith will have an assortment of specialized tools that are specifically designed for dealing with broken and stuck keys.

What to Do Next

Once you have the broken key out of the lock, resist the temptation to glue both halves back together and use the key. Chances are the key will just break within the lock and you'll have to perform the extraction all over again. Instead, have your locksmith piece the key together and cut a new copy from the original key.