Getting an accurate square footage number before you call a fabricator saves time and gives you a realistic budget. This guide walks through every layout type - straight runs, L-shapes, U-shapes, and islands - with diagrams and worked examples.
Before grabbing your tape measure, spend two minutes drawing a rough top-down sketch of your kitchen. It doesn't need to be to scale - just identify how many separate counter runs you have and label each one (A, B, C).
Most kitchens fall into one of four layouts. Find yours in the diagrams below - you'll measure each lettered section separately and add the results together.
Depth is the distance from the wall to the front edge of the counter. Measure this for each run - don't assume all runs are the same depth, especially in older kitchens or bathrooms.
Standard depths to know: Kitchen countertops are typically 25 inches (24" cabinet + 1" overhang). Bathroom vanities are usually 21–22 inches. Islands with seating overhangs can be 30–42 inches on the seating side.
Measure from the back wall (or backsplash) to the very front edge of the overhang. Write down the depth for each section on your sketch.
For a straight run, measure from wall to wall (or wall to edge of the counter, if it ends before reaching a wall).
For an L-shape, measure each leg from the outside corner to the end of that run. Do not measure across the corner - treat each leg as its own rectangle.
For a U-shape, measure all three runs independently: the back wall run, the left side run, and the right side run.
Measure to the nearest ¼ inch. Rough estimates in feet alone can be off by a full square foot on a typical kitchen, which translates to a noticeable pricing difference.
Use this formula for each section, then add all sections together:
You can also convert to feet first if that's easier: divide each measurement in inches by 12, then multiply length × depth.
Quick reference - common lengths at standard 25" depth
| Length | Depth | Square footage |
|---|---|---|
| 4 ft (48") | 25" | 8.3 sq ft |
| 5 ft (60") | 25" | 10.4 sq ft |
| 6 ft (72") | 25" | 12.5 sq ft |
| 8 ft (96") | 25" | 16.7 sq ft |
| 10 ft (120") | 25" | 20.8 sq ft |
| 12 ft (144") | 25" | 25.0 sq ft |
A cutout is any hole cut into the slab for a sink, cooktop, or faucet. Here is the rule most fabricators follow:
Do not subtract cutouts from your square footage. The fabricator still buys the full slab and the offcut is not reusable. Most include one cutout (usually the kitchen sink) in the price and charge a small fee for additional cutouts.
When getting your quote, ask the fabricator specifically: "Is the sink cutout included, or is it an extra charge?" Standard sink cutouts are typically $100–$200 extra; cooktop cutouts are similar. Faucet holes are usually $20–$50 each.
Once you have your total square footage, multiply by 1.10. This 10% buffer accounts for:
For natural stone with strong veining (Calacatta marble, exotic granites), some fabricators recommend 15% overage because pattern matching requires more offcuts. Ask your fabricator when getting the quote.
A homeowner has an L-shaped kitchen. Here's their measurement process from start to finish:
| Section | Length | Depth | Square footage |
|---|---|---|---|
| A - back wall run | 108" (9 ft) | 25" | 108 × 25 ÷ 144 = 18.75 sq ft |
| B - side wall run | 72" (6 ft) | 25" | 72 × 25 ÷ 144 = 12.50 sq ft |
| Raw total | 31.25 sq ft | ||
| + 10% overage | 34.4 sq ft → 35 sq ft | ||
This homeowner would enter 35 sq ft into the cost calculator to get their estimate.
Enter your square footage, pick your material and region, and get an instant price range - then request a free quote from local fabricators.