Home lock calculator
Master Key Access Planning Tool
Map doors and access groups before requesting a professional master-key system.
Result
Change keys to issue
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System setup estimate (USD)
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Keys and cylinders to track
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Formula
Calculation logicRekey, Keyed-Alike, and Key Control
Rekey beats replace when hardware is sound
Rekeying (~$25 per cylinder) wins whenever the lock operates smoothly and cylinders share a keyway. Replace the full set when hardware is damaged, forced, or corroded, and replace cylinders first when brands are mixed.
Run two key groups at most
One shared key for convenience areas, one restricted key for rentals, offices, and utility rooms. Lost keys and tenant turnover force an immediate rekey before new copies go out. Log every key by person and date; collect all copies on move-out.
Verify before you buy
- Map groups to doors on paper
- Require written key-control policy