BuildDecide

Countertop Calculator

Estimate your countertop project — slab area, backsplash, cutouts, and total installed cost.

By BuildDecide Editorial Team — Updated

Before you start

Have your room dimensions ready. All inputs default to common sizes so you can see a worked example instantly.

ft

Add up every run: perimeter counters plus island. A typical kitchen is 15–25 ft total.

in

24" is standard base cabinet depth. Stone often finishes at 25" with overhang; islands run 36" or more.

in

4" is the standard short splash. 18–24" for full-height slab. Enter 0 if you are using tile instead.

$

Quoted $/sq ft for material + fabrication + install. Laminate $20–45, solid surface $35–75, quartz/granite $50–90, premium $90–120+.

Undermount sinks usually need a polished cutout. Add one per sink — a wet bar counts.

Drop-in cooktops and slide-in ranges need a cutout. A freestanding range does not.

ft

Linear feet getting an upgraded edge (ogee, mitered, waterfall). Leave 0 if a standard eased edge is included.

%

Covers seams, cutoffs, and sink cutouts. 10% for straight runs; 15–20% for islands, miters, or waterfall edges.

Total installed cost$3,61251 sq ft at $65/sq ft plus $275 in cutout and edge fees.
Countertop area4020 ft of run at 24" deep. This is the surface you actually see.
Slab area to order51Includes 10% waste. Order this much material — you pay for what is cut off.
Material + installation$3,337Slab, fabrication, template, and install labor at your quoted rate.
Cutout & edge fees$275Charged on top of the per-square-foot rate, not included in it.
Cost per linear foot$181Useful for comparing quotes at a glance — ask each fabricator for this number.
What's next?

Cost estimated? Check it against 2026 countertop installation prices, compare quartz vs granite, or budget the whole kitchen remodel.

How countertop pricing actually works

Almost every fabricator quotes countertops per square foot installed — one number that bundles the slab, fabrication, template, and install labor. That number is the input this calculator is built around, because it is the one you will actually be given.

The catch: the per-square-foot rate only covers the flat top. Cutouts, edge upgrades, and backsplash are usually billed separately, and they are where quotes quietly diverge. This calculator keeps them as separate line items so you can see what is driving the total.

The area math

  • Countertop area = total run length × (depth ÷ 12). A 20 ft kitchen at 24" deep is 40 sq ft.
  • Backsplash area = total run length × (height ÷ 12). A 4" splash on the same 20 ft is 6.7 sq ft; a full-height 18" splash is 30 sq ft.
  • Order area = (counter + splash) × (1 + waste).

You are billed on order area, not finished area. Stone comes in slabs, and every cut leaves a remnant you paid for. That is what the waste allowance represents.

Installed price per square foot, by material

Material Installed $/sq ft Notes
Laminate $20 – $45 Post-formed tops with integrated splash are cheapest. Not repairable if burned.
Butcher block $30 – $60 Needs oiling 2–4× per year. Sink cutouts must be sealed.
Solid surface $35 – $75 Seams sand out invisibly; can be repaired. Scratches more than stone.
Quartz $50 – $90 Engineered, non-porous, no sealing. Most of the mid-range market.
Granite $50 – $90 Natural variation, needs sealing. Price swings with slab availability.
Premium quartzite / marble $90 – $120+ Exotic slabs, book-matched or waterfall installs.

Worked example: 20 ft kitchen, mid-range quartz

  • Countertop area: 20 ft × 24" deep = 40 sq ft
  • Backsplash: 20 ft × 4" = 6.7 sq ft
  • Order area with 10% waste: 46.7 × 1.1 = 51 sq ft
  • Material + install at $65/sq ft: 51 × 65 = $3,337
  • One sink cutout + one cooktop cutout: 150 + 125 = $275
  • Total: about $3,612, or $181 per linear foot

That $181/linear ft figure is the one to hold onto. When you collect quotes, ask each fabricator for their cost per linear foot — it normalizes for kitchen size and makes comparison immediate.

What actually moves the price

Edge profile. A standard eased or bevel edge is usually included. Ogee, bullnose, mitered, and laminated edges add $10–$30 per linear foot — and a waterfall edge is a different order of cost entirely, since it needs a mitered joint at each end and matching grain.

Full-height backsplash. Going from a 4" splash to 18" adds 23 sq ft on a 20 ft run. At $65/sq ft that is roughly $1,650 more — more than most people expect, because the splash is priced at the same rate as the top even though it is a simpler piece.

Islands. An island is not just more square footage. If it is over 24" deep it may need a seam, and any overhang past 12" needs corbels or steel support. Islands also push waste up: they are often cut from a second slab.

Seams. Slabs are typically 55–65 sq ft. A 20 ft run at 24" deep is 40 sq ft of top, but it is 20 ft long — longer than most slabs. That forces at least one seam, placed where it is least visible. Seam count is a labor driver, not a material one.

What this calculator does not include

  • Tear-out and disposal of the old countertop — $200–$600 typical, more for tile
  • Plumbing disconnect and reconnect for the sink — $150–$400, and often requires a plumber
  • Electrical for a new cooktop or under-cabinet outlets
  • Cabinet leveling or repair — stone countertops do not forgive an uneven cabinet run
  • Taxes, delivery, and crane fees for upper-floor or hard-access installs

Budget 10–20% on top of your calculated total for these.

Getting a quote that holds

Ask for the quote itemized: slab cost, fabrication, template fee, cutouts, edge, backsplash, and install — separately. A single lump-sum per-square-foot number is where surprises hide. Also confirm whether the template visit is included and whether the price locks once the slab is selected.

Compare against our countertop installation cost guide for 2026 price tiers, and see quartz vs granite for the material decision.

Common sizes at a glance

Pre-computed results for typical sizes using this calculator’s standard assumptions — adjust the inputs above for your own numbers.

SizeTotal installed costCountertop areaSlab area to orderMaterial + installation
12 ft galley kitchen$2,2772431$2,002
20 ft kitchen$3,6124051$3,337
30 ft kitchen with island$5,2806077$5,005
20 ft kitchen, laminate at $30/sq ft$1,8154051$1,540
20 ft kitchen, premium stone at $110/sq ft$5,9224051$5,647
20 ft kitchen, full-height backsplash$5,2804077$5,005

Industry benchmarks

Standard base depth24" — stone finishes at 25" with overhang
Typical total run (kitchen)15–25 linear ft including island
Standard backsplash4" — full-height is 18–24"
Typical slab size55–65 sq ft — a 20 ft run usually needs 2
Sink cutout$100–$300 depending on material and edge polish
Premium edge upgrade$10–$30 per linear ft over eased edge
Tear-out of old top$200–$600, more for tile

Frequently asked questions

How much do countertops cost for a 20 ft kitchen?

A 20 ft run at standard 24" depth is 40 sq ft of countertop. With a 4" backsplash and 10% waste that is about 51 sq ft to order. At the mid-range quartz rate of $65/sq ft installed that is roughly $3,300, plus $275 for a sink and cooktop cutout — about $3,600 total, or $181 per linear foot. Laminate at $30/sq ft would be about $1,800 for the same kitchen; premium quartzite at $110/sq ft would be about $5,900.

Should I allow waste on a countertop estimate?

Yes — 10% minimum, and more for islands or miters. You are billed for the slab area the fabricator cuts from, not the finished counter. Sink cutouts, the strip removed for a seam, and slab-end cutoffs are all material you paid for and cannot use. Islands often force a second slab, which can push effective waste past 20%.

How much does a full-height backsplash add?

It is priced at the same per-square-foot rate as the countertop, which makes it more expensive than most people expect. On a 20 ft run, going from a 4" splash (6.7 sq ft) to an 18" splash (30 sq ft) adds about 23 sq ft — roughly $1,500 at $65/sq ft, or about $2,600 at a premium $110/sq ft rate. Backsplash tile is often a cheaper alternative if you like the look.

Why do fabricators charge extra for cutouts?

Cutouts are hand work, not slab area. An undermount sink cutout needs a precisely polished inner edge, and it has to be done after templating so the sink aligns with the cabinet. Typical charges are $100–$300 per sink cutout and $75–$250 per cooktop cutout, and the fee does not vary much with the size of the kitchen — which is why cutouts hit small kitchens harder.

How long is a countertop slab, and will I need a seam?

Most slabs are 55–65 sq ft, commonly around 120" × 55" to 130" × 63". A 20 ft counter run is longer than any single slab, so it needs at least one seam. Fabricators place seams at the least visible point — often at the sink or a natural break. Longer runs, islands, and waterfall edges all add seams, and seam count drives labor more than slab cost.

Is quartz or granite cheaper?

At the entry and mid tiers they are very close — both commonly land in the $50–$90 per square foot installed range, and the difference usually comes down to which slabs the local yard has in stock. Quartz is engineered, so pricing is more consistent and it never needs sealing. Granite varies slab to slab, and a distinctive or rare slab can push past $100/sq ft. See our quartz vs granite comparison for the full trade-off.

Does this calculator include removing my old countertops?

No. Tear-out and disposal typically add $200–$600, and more if you are removing tile set in mortar or a solid surface glued to the cabinets. Plumbing disconnect and reconnect for the sink is separate again, usually $150–$400 and often requiring a licensed plumber. Budget 10–20% above the calculator total to cover these.

How accurate is a per-square-foot quote?

It is accurate for the flat top and misleading for everything else. Two fabricators can quote the same $65/sq ft and land $1,000 apart once edge profiles, cutout fees, seam placement, and backsplash are priced. Ask for an itemized quote — slab, fabrication, template, cutouts, edge, splash, install, tear-out — and compare line by line rather than comparing the headline rate.

Related calculators

Tile Calculator
Order the right number of tiles — with waste for cuts, breakage, and pattern layout.

Related cost guides

Countertop Installation Cost in 2026
Budget new countertops with realistic 2026 installed prices — from laminate to natural stone.
Kitchen Remodel Cost in 2026
Plan your 2026 kitchen budget with low, mid, and high-end ranges — before you call a contractor.

Related comparisons

Quartz vs Granite Countertops — Which Should You Choose?
Engineered consistency vs natural stone character — the countertop decision explained.

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