Countertop Square Footage Calculator
Measure kitchen and bathroom countertop area to estimate slab material - granite, quartz, marble, butcher block, or laminate. Most fabricators charge per square foot of finished surface.
Countertop Area Calculator
Measuring countertop runs
Break your kitchen into separate runs: main run, peninsula, island, and any return walls. For each run, measure length along the front edge × depth (front-to-back including overhang). For an L-shaped kitchen, measure each leg as a separate rectangle and sum.
Standard kitchen countertop depth is 25.5 in (2.125 ft) - cabinet box is 24 in plus a 1.5 in front overhang. Most stone fabricators expect this depth unless you specify deeper. Bathroom vanities are usually 22 in deep (1.83 ft).
Stone slab planning
Granite and quartz typically come in slabs around 9 ft × 5 ft 6 in (~50 sq ft per slab), though sizes vary by stone and supplier. A typical kitchen needs one full slab plus part of a second to allow for graining direction, the sink cutout, and seam placement.
Fabricators charge for the full slab usage, not just your finished area. A 50 sq ft kitchen often requires 60-70 sq ft of slab purchased. Always have the fabricator template after cabinets are installed - paper templates from drawings rarely match real-world conditions.
Calculating countertop square footage
Countertops are typically priced by the square foot of installed surface, but the calculation isn't as simple as length × width because of overhangs, sink cut-outs, and bumped-out areas.
Base measurement: linear feet of cabinet run × counter depth. Standard counter depth is 25.5 inches (2.125 ft). For a 10 ft galley counter: 10 × 2.125 = 21.25 sq ft of base counter.
Add overhangs: standard counter overhang is 1 inch beyond cabinet face on both sides; not significant for most layouts. Bar overhangs (typically 12 inches) add 1 sq ft per linear foot of bar.
Add islands separately: a 4 × 6 ft island = 24 sq ft. Add 6 inches all around for typical overhang: 5 × 7 = 35 sq ft. Islands often account for 40-60% of a kitchen's total counter square footage.
Don't subtract for sink cut-outs in the square footage calculation. The slab fabricator needs the full slab area to cut out of, even though the sink hole is removed.
Material costs per square foot
Countertop materials span an enormous price range, from $20/sq ft for basic laminate to $200+/sq ft for exotic natural stones.
Laminate (Formica, Wilsonart): $20-40/sq ft installed. Includes the substrate.
Tile counters: $10-30/sq ft DIY, $40-60 installed. Less common today but cheap.
Butcher block (maple, walnut): $40-100/sq ft installed. Requires regular oiling.
Granite: $50-100/sq ft installed for standard tiers, $100-200 for exotic colors and patterns.
Quartz (Caesarstone, Silestone, Cambria): $50-120/sq ft installed. Most popular premium option in 2024.
Marble (Carrara, Calacatta): $75-200/sq ft installed. Stains easily — not ideal for kitchens.
Soapstone: $60-100/sq ft installed.
Concrete (custom poured): $80-150/sq ft installed.
Quartzite (true quartzite, not engineered quartz): $80-200/sq ft installed.
What 'installed' includes — and doesn't
When a fabricator quotes $80/sq ft installed quartz, the price usually includes: standard slab, fabrication, edge profile (eased or square), sink cut-out, faucet holes, and basic installation. It typically does NOT include:
Removal of existing countertops ($3-8/sq ft separately).
Plumbing disconnect and reconnect ($150-400).
Upgraded edge profiles (ogee, bullnose, mitered: +$10-30/sq ft).
Backsplash made from the same material (priced separately).
Cut-out for stovetop ($50-150 per cut-out).
Cooktop or sink template work ($75-200).
Built-in soap dispensers, instant-hot taps, prep sinks (extra holes: $50 each).
Always get the itemized quote before signing. The advertised $/sq ft is rarely the all-in number.
Pro tips
Count seams in your design
Most slabs max out at 9-10 ft. Runs longer than that will have a seam. Decide where the seam goes BEFORE templating - usually at a sink or cooktop, never on a long unbroken run.
Add for overhangs and waterfalls
Standard 1.5 in front overhang is included in 25.5 in depth. Bar overhangs (12 in for seated counters) and waterfall ends add square footage - measure them separately.
Sink and cooktop cutouts are billed
Fabricators charge for cutouts even though material is removed. The cutout fee covers labor and the unused stone scrap.
Bookmatch slabs for veining
For high-veining stones, request bookmatched slabs and look at them in person before ordering. The whole-slab look depends on which slab you choose.