Gabion calculator
Boxes for a gabion wall or a known volume, the stone to fill them, and the filter geotextile behind the wall.
Free access for engineers and buyers
Sign in with a one-time code: no password to remember. All ten Retech calculators then open on this device, and your details reach the Retech desk so an engineer can help with your project. We do not share them.
Results appear here as you type.
How the calculation works
Courses are wall height ÷ box height, rounded up; boxes along the wall are wall length ÷ box length; boxes across each course narrow evenly from the base width to the top width. Stone is the gabion volume × filled density, about 1.7 t/m³ for stone at 35% voids. Example: a 50 m wall, 3 m high, 2 m wide at the base and 1 m at the top, in 2 × 1 × 1 m boxes, needs 125 boxes, 250 m³ and about 425 t of stone. The filter geotextile behind the wall is RNW 300 GSM.
Planning quantities for budgeting and enquiry. A Retech engineer confirms the grade and quantity against your drawings before order.