Calculator
Enter your measurements and options. On large screens the form uses three columns, two on medium, and one on mobile.
Formula Used
This calculator estimates total ladder tape required using a simple material model:
- Effective drop = finished drop + top allowance + bottom allowance
- Total tape (no waste) = effective drop × ladder count × sides per ladder
- Total tape (with waste) = total tape × (1 + waste% ÷ 100)
Tip: If your build needs extra length for stitching loops at every slat, increase the waste factor or allowances to match your method.
How to Use This Calculator
- Measure the finished blind drop you want installed.
- Add top and bottom allowances for your build style.
- Enter how many ladders run across the blind width.
- Keep sides per ladder at 2 for most designs.
- Use a 5–10% waste factor for cutting and adjustments.
- Press Calculate and download CSV or PDF if needed.
Example Data Table
Sample scenarios to compare tape needs across sizes.
| Unit | Finished Drop | Top Allow | Bottom Allow | Ladders | Sides/Ladder | Waste % | Total With Waste |
|---|---|---|---|---|---|---|---|
| cm | 160 | 10 | 10 | 3 | 2 | 7 | 1099.2 cm |
| cm | 220 | 15 | 12 | 4 | 2 | 8 | 2134.1 cm |
| in | 72 | 4 | 4 | 3 | 2 | 6 | 483.36 in |
These examples are illustrative. Always validate against your ladder tape product specs and assembly method.