How Do I Unlock a Deadbolt Without a Key?

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If the lock is a single-cylinder deadbolt and the knob inside the door is accessible turning the knob opens the lock. If the lock is a double-cylinder lock or the inside of the door is not accessible, special lock picking tools are necessary. If the deadbolt is not fully locked into position, pressing a credit card or other flat tool into the space left by the partially opened deadbolt allows it to open. Completely locked deadbolts require special lock picking tools to open.