Home & Business Security Tools & Calculators
Free, practical tools to plan and improve your security — from locks and deadbolts to smart locks and keypads, cameras and CCTV, alarms, safes, and access control.
Keypad Combination Calculator
See how many codes a keypad lock or PIN pad can hold, and how long a brute-force attacker would need — with code length, keypad size, no-repeat rules, and lockout all in play
Security Camera Storage Calculator
Size the NVR/DVR drive your CCTV system needs from resolution, frame rate, recording hours, retention days, and camera count — in GB and TB, with a suggested drive size
Password Entropy Calculator
Measure a password's strength in bits of entropy from its length and character sets, and estimate how long an offline attacker would take to crack it at a chosen guessing speed
Camera Lens Coverage Calculator
Work out a security camera's horizontal field of view and how wide a scene it captures at a given distance, from its focal length and sensor size — real optics, no guesswork
Lock Grade Guide (ANSI/BHMA)
Compare ANSI/BHMA Grade 1, 2, and 3 for deadbolts and locksets on the exact cycle counts, forced-entry strikes, and strength each must pass — and which grade fits your door
Safe Rating Guide (UL Fire & Burglary)
Decode UL fire ratings (Class 350, 150, 125) and burglary ratings (RSC, TL-15, TL-30, TL-30x6) and filter them by whether you need fire protection, burglary protection, or both