Anchor Bolts – Count, Size & Embedment

A reliable anchor bolts takeoff follows one rule: measure twice, order once. The calculator converts your plate length, bolt grade and concrete strength into dependable quantities using Count = Plate Length ÷ 1.8 + 2; Embed = 8 × Ø; Min 4 bolts per plate, then adds the waste margin that experienced builders apply by default. Example: A 12 m sill plate: 12 ÷ 1.8 + 2 = 9 M12 bolts, embedded 100 mm, each resisting 8-12 kN shear. Field tip: Wet-set bolts before the pour or drill after - halfway marks never hold torque. The result is broken down into purchasable units - bags, sheets, rolls or truck loads - so you can order the nearest whole unit without overbuying, and every figure traces back to the formula shown above.

1. 1

   Measure the space

   Record the plate length, bolt grade and concrete strength at the widest and longest points.

2. 2

   Enter the values

   Type the measurements into the calculator and select your units.

3. 3

   Apply the formula

   The tool computes Count = Plate Length ÷ 1.8 + 2; Embed = 8 × Ø; Min 4 bolts per plate for your inputs instantly.

4. 4

   Add waste and order

   Review the total with a 5-10% margin and round up to whole units.

• Weight from wrong diameter

• Exceeding conduit fill

• No lap splice allowance