Siding Square Footage Calculator
Just need the number? Get your net siding area in square feet and squares — walls plus gables, minus every opening.
Walls (feet)
Gables / triangles optional
Windows & doors to subtract
Tip: measure each wall's width × height at its widest points. A per-wall audit table appears below so you can check every number.
Your siding squares, panels and cost appear here.
Estimated from wall count and perimeter — confirm against your actual corners and openings.
Cost per sq ft: – · per square: –
| Surface | Area (sq ft) |
|---|
Square footage without the extras
Sometimes you don't want a full materials order or a cost estimate — you just need clean square footage to hand to a supplier or drop into another tool. This page strips it back to that: enter your walls and gables, subtract the openings, and read net area in both square feet and squares. No panels, no boxes, unless you want them.
Square footage is the foundation everything else is built on, so getting it right here means every downstream number — material, cost, paint — is right too. The per-wall audit lets you verify each surface.
Step-by-step: from tape measure to order
The whole process is measure, subtract, pad, convert. Here's how that maps onto the fields above.
- Set your basics. Units and material at the top control everything downstream, so start there.
- Walls, one at a time. Enter width × height × quantity for each face of the house.
- Triangles and cut-outs. Add gable base and rise; subtract every significant window and door.
- Cushion and cost. Choose a waste percentage and, if you're budgeting, set labor and removal rates.
- Review the breakdown. Check the per-wall audit, then print or share.
Sq ft to squares
Divide any square footage by 100 to get squares: 1,850 sq ft is 18.5 squares. That single conversion is what turns a tape-measure number into something a siding supplier can quote from.
About the accuracy of these results
We'd rather be transparent than falsely precise. The quantity math is deterministic and matches standard takeoff practice, so if your inputs are right, your squares and piece counts are right. Where real-world variation lives — coverage by profile, and installed cost by region and crew — we use typical published figures and present them as ranges. That makes this a strong planning number, not a binding quote; a contractor's field measure remains the final word.
From square footage to a finished order
Net area is the number everything else depends on. Once you trust it, here's how it flows into the rest of your project.
- To squares: divide by 100. Suppliers quote and price in squares, so this is the unit to shop with.
- To material: divide the padded area by your product's coverage per piece for panels or boards.
- To paint: for a coating job, divide net area by the paint's coverage per gallon and double for two coats.
- To cost: multiply by an installed rate per square foot for a quick budget check.
Because every downstream number leans on this one, use the per-wall audit above to confirm each surface before you rely on the total.
Frequently asked questions
How do I calculate siding square footage?
Do I subtract windows and doors from siding square footage?
How do I convert square footage to squares?
Should I include the gable triangles?
From people who've used it
"Exactly what I needed — clean square footage, no upsell. Fed it straight into my supplier's system."