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Siding Square Footage Calculator
Just the area — no material, no cost, no extra steps.
Why this one's different
Our other calculators estimate materials and cost for a specific siding product. This one skips all of that — if you just need your home's exterior wall square footage for a painting quote, an insurance form, or your own records, this gives you that number in three fields with nothing else to fill in.
Square Footage Calculator
Enter your home dimensions to get the total area.
Square Footage: Common Questions
What this number is for, and how it differs from a siding quote.
How is exterior wall square footage calculated?
For a simple rectangular wall, multiply width by height. For a whole house, add up every exterior wall this way, add any gable (triangular) sections, then subtract the area of windows and doors — since siding doesn't cover glass or door openings. That's exactly what this calculator does across the Walls, Gables, and Openings tabs.
Is siding square footage the same as a home's total square footage?
No — these are two completely different numbers. A home's "total square footage" (used in real estate listings) measures interior floor area. Siding square footage measures the exterior wall surface area, which depends on wall height and shape, not floor space. A single-story house and a two-story house can have identical floor square footage but very different wall square footage.
Do I need to subtract windows and doors for an accurate number?
For a true siding-material estimate, yes — siding doesn't get installed over glass or door openings. For rougher purposes like a quick painting estimate or a general reference number, some people skip this step since window and door area is often a small percentage of total wall area on an average home.
Should I add a buffer percentage to this number?
If you're using this figure to compare against a material-specific calculator, leave the buffer at 0% and use the exact area. If you want a small safety margin for measurement error on your own tape-measure numbers, a 5% buffer is a reasonable, conservative addition.