Crack Detector - Crack Gauge

Crack Detector finds cracks in concrete and walls from a photo taken with your phone, then measures their width and length.

Machine learning locates the crack and traces its outline. Print the marker, place it next to the crack, and take the photo — the marker becomes the ruler, and width and length come out in millimeters. Without a marker the result is recorded as a relative value, and the app keeps the two clearly apart by color and shape.

■ Measure
• Analyzed right after you shoot — position, width, length
• Millimeters with a marker, relative (pixel) values without — never confused
• Multiple markers crop the photo to the area you care about
• Site name, location and time are recorded with every measurement

■ Dashboard
• Width distribution — which size range your cracks fall in
• Site comparison — which site is worse, by median and maximum width
• Widest cracks — where to look first
• Measurements by month

■ Sites
• Pick one site and see its summary, distribution and every measurement

■ Map
• Every measurement on a map. Measurements at the same spot are grouped so none is hidden
• Measured and relative values told apart by color

■ Records
• Search by period and site name, mark favorites
• Export to Excel (xlsx) with images and values
• Zoom into the result image next to the original

■ Points
• 10 free analyses when you sign up
• Top up 10 or 100 at a time, as much as you need

■ Also
• Korean, English, Japanese
• Sign in with Apple, Google or email
• Dark mode

The marker can be printed from "Marker Guide" inside the app. Acceptable crack widths depend on the structure, environment and design code, so the app does not grade severity — it shows you the measurement.