Inputs
Units: Imperial
For identical plates with the same hole pattern.
For reference only; diameter does not affect counts.
Building axis length.
Building axis width.
Typically 2 (top and underside). Adjust for design.
Set 0 if not required; double-nut use 2.
Covers loss, damage, site spares.
Tip: Press Ctrl+L to highlight URL, share with inputs.
Results
| Metric | Value |
|---|---|
| Total plates | - |
| Holes per plate | - |
| Raw bolt count | - |
| Raw washer count | - |
| Raw nut count | - |
| Waste factor | - |
| Final bolts | - |
| Final washers | - |
| Final nuts | - |
| Bolt packs required | - |
| Washer packs required | - |
| Nut packs required | - |
Example Data
| # | Description | Plates | Holes/Plate | Washers/Bolt | Waste % | Bolts | Washers |
|---|
Modify inputs and press Calculate to refresh results above.
Formula used
By plate count: Plates = entered value.
By grid area: Along each direction, usable span = Span - 2×Edge Setback. Number of positions = floor(Usable/Spacing) + 1. Plates = PositionsX × PositionsY.
Raw bolts: Plates × HolesPerPlate.
Raw washers: RawBolts × WashersPerBolt.
Raw nuts (optional): RawBolts × NutsPerBolt.
Waste: Multiply each raw quantity by (1 + Waste%/100) and round up to the next whole number.
Packs: ceil(FinalQty / PackSize).
These formulas provide practical estimates. Always verify against project specifications and applicable standards.
How to use
- Select By plate count for identical plates, or By grid area to derive plates from area and spacing.
- Enter holes per plate, washers per bolt, optional nuts per bolt, and waste percentage.
- Enter pack sizes to see required package counts for ordering.
- Press Calculate. Review results and adjust as necessary for site spares.
- Use Download CSV or Download PDF to attach to submittals or purchase orders.
Switch units label using the toggle below; dimensions are treated numerically for counting.
FAQs
Two is common—one under the nut and one under the baseplate. Some designs add a lock washer; always follow project drawings and manufacturer guidance.
No. Counts are driven by plate quantity and hole pattern. Diameter influences strength and washer/nut sizing, not the arithmetic of quantities.
Many projects use 3–10% to cover damage, lost pieces, and spares. For critical works or remote sites, consider more based on risk and logistics.
Yes. Enter pack sizes for bolts, washers, and nuts. The calculator reports both final parts and the number of full packs required.
We subtract edge setbacks from each side, divide by spacing, take the floor, and add one position per direction. Multiplying positions in X and Y gives plate count.