Broken Key: What To Do

You're standing at your front door after a long day, you give the key a firm turn, and then it happens. A snap. Half the key is in your hand and the other half is stuck inside the lock cylinder. It's frustrating, occasionally embarrassing, and can leave you completely locked out of your home.

The good news is this is one of the more common locksmith call-outs in Australia, and there are several ways to handle it depending on how deep the broken piece is, what tools you have available, and your level of DIY confidence. This guide walks you through your options clearly and honestly.

Keys don't usually snap without warning signs. Understanding the cause helps you avoid it happening again.

Metal Fatigue

Keys are stamped from brass or nickel silver blanks. Over time, repeated bending forces, even very slight ones caused by a stiff lock, create micro-fractures. Eventually the metal gives way, usually right at the bow (the part you grip) or at the first cut near the shoulder.

A Worn or Dirty Lock Cylinder

When a lock cylinder hasn't been lubricated or serviced in years, the pins bind against the key. Forcing a stiff lock is one of the fastest ways to snap a key. Deadbolts and older rim locks are frequent offenders.

A Copied Key That Wasn't Cut Cleanly

Poorly cut duplicate keys sometimes have slightly off dimensions, which increases friction inside the cylinder. If you're using a copy rather than the original, inspect it closely for rough edges or uneven cuts.

Before reaching for a tool or calling a locksmith, check two things:

How Much of the Key Is Exposed?

If 5mm or more of the broken key is protruding from the keyway, you have a reasonable chance of removing it yourself. If the break point is flush with the face of the lock or recessed inside the cylinder, DIY extraction becomes much harder and more likely to cause further damage.

Is the Lock in the Locked or Unlocked Position?

If the key snapped while fully turned, the cylinder may be in the unlocked position, meaning the door is still openable. Try turning the lock body with pliers or a flat screwdriver before anything else. If the door opens, you're no longer locked out, though you'll still need to extract the broken key before using the lock again.

These methods work best when part of the key is still visible outside the keyway.

Needle-Nose Pliers

If enough of the broken key is exposed, grip it firmly with needle-nose pliers and pull straight out, not at an angle. Wiggling sideways can push the fragment deeper. This is the safest and simplest DIY option.

Broken Key Extractor Tool

These small hooked tools are sold at hardware stores like Bunnings or online for around $10 to $20. Slide the extractor alongside the key fragment in the keyway, hook the teeth of the key with the tool's barb, and pull. It takes a little patience but works well on standard pin tumbler locks. A set of extractors in different profiles is useful to have in your toolbox.

Jigsaw Blade Fragment

If you don't have an extractor, a thin jigsaw blade snapped to about 50mm can act as a makeshift hook. File or grind a small notch near the tip, insert it beside the key fragment, and attempt to hook and drag the piece out. This is a last resort and can scratch the cylinder internally.

What Doesn't Work

Superglue on the key stub is a popular suggestion online. In practice it rarely works and frequently bonds the key fragment permanently to the cylinder, making professional extraction far more difficult and expensive. Avoid it entirely.

If the fragment is flush or recessed, if you've already attempted extraction and it hasn't moved, or if the lock is a high-security cylinder like a Mul-T-Lock or Abloy, stop and call a professional. Forcing the issue risks damaging a lock that might otherwise be saved.

What a Locksmith Will Do

A qualified locksmith carries professional extraction tools including plug followers, tension wrenches, and purpose-built broken key extractors. Most standard extractions take 10 to 20 minutes. If the cylinder is damaged, they may recommend rekeying or replacing it on the spot.

What It Should Cost in Australia

Based on Reddit discussions from Australian homeowners, after-hours call-outs typically land between $130 and $180 for a straightforward job. Be cautious of any locksmith quoting under $50 for after-hours work, that's a common bait-and-switch tactic. Always ask for a quote before they begin work.

There are over 570 emergency locksmith businesses listed nationally, with strong coverage in Melbourne (178 listings), Sydney (150), Brisbane (68), Perth (67), Adelaide (46), and the Gold Coast (33). Businesses like Terry's Locksmiths (4.9 stars), Tas Mobile Locksmith (5.0 stars), and Express Locksmith Gold Coast & Tweed (5.0 stars) are examples of highly rated operators with thousands of verified reviews. The average rating across Australian emergency locksmiths sits at 4.8 out of 5.

Once the broken fragment is removed, you have a few decisions to make.

Check the Condition of the Lock

Ask your locksmith to inspect the cylinder for internal damage. A pin tumbler cylinder that's been forced or scratched internally may feel loose or operate inconsistently afterward.

Get a New Key Cut

If the lock is in good shape, have a new key cut from your original or from the lock's code if the manufacturer can supply it. A local key cutting service at a hardware store or locksmith typically charges $5 to $15 for a standard residential key.

Consider Rekeying

If the broken key was also your only copy, or if you've had the same lock for more than five years without rekeying, this is a good opportunity to rekey the cylinder. It gives you fresh keys and eliminates any risk from lost or unaccounted copies.

A few simple habits will significantly reduce the chance of another snapped key.

• Lubricate your locks with a PTFE or graphite-based lubricant twice a year, especially on external doors exposed to weather.
• Never force a stiff lock. If a key is hard to turn, have the lock serviced rather than applying more pressure.
• Inspect your keys annually for hairline cracks near the shoulder or along the blade. If you can see a crack, replace the key before it snaps.
• Use original keys for daily use and keep copies as true backups, not primary keys.