Enter your surface dimensions and sealer type to instantly calculate gallons needed, container counts, and total cost estimate — for one coat or multiple.
Free to use
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Coverage rates from manufacturer data
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Imperial supported
✓ All sealer types covered✓ 1-gal & 5-gal container counts✓ Multi-coat support✓ Last verified May 2026
Longest dimension of the surface to be sealed.Please enter a valid length greater than 0.
Shorter dimension of the surface.Please enter a valid width greater than 0.
Selects the standard coverage rate for that sealer. Adjust manually if your product differs.
Check your product label — actual rate varies by product and surface porosity.Please enter a valid coverage rate greater than 0.
Most penetrating and acrylic sealers require 2 coats. Epoxy and polyurethane may need 2–3.
Add 10% for standard rectangular surfaces. Add 15–20% for porous surfaces or irregular shapes.
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Leave blank to skip cost estimate. Typical range: $20–$80/gal depending on sealer type and brand.
Results appear instantly. No sign-up required.
Your Sealer Estimate
Sealer Volume Required (with waste)
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Total Gallons
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Gallons Per Coat
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Surface Area (sq ft)
Containers to Purchase
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1-gallon containers
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5-gallon pails
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Optimal mix (5+1 gal)
—Coats
—Coverage Rate
—Waste Factor
—Area (m²)
Estimated Material Cost
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Sealer material cost only. Add labor ($0.50–$1.50/sq ft), surface prep, and equipment rental for a full project budget.
Step 1: Convert dimensions to feet → Area (sq ft) = Length (ft) × Width (ft)
Step 2: Gallons per coat = Area ÷ Coverage Rate (sq ft/gal)
Step 3: Total gallons (before waste) = Gallons per coat × Number of coats
Step 4: Total gallons (with waste) = Total × (1 + waste% ÷ 100)
Step 5: 1-gal containers = CEIL(Total gallons)
Step 6: 5-gal pails = CEIL(Total gallons ÷ 5)
Step 7: Optimal mix = FLOOR(Total ÷ 5) pails of 5-gal + CEIL(remainder) of 1-gal
How to Use This Concrete Sealer Coverage Calculator
Measure the surface to be sealed.
Measure the length and width of the area in feet. For irregular shapes — L-shapes, curves, or spaces with cutouts — break the area into rectangles, calculate each separately, and add the results together. For existing surfaces, measure inside the control joints or edge trim, not the exterior boundaries of the formwork.
Select your sealer type and confirm the coverage rate.
Use the quick-select preset buttons to auto-fill the standard industry coverage rate for your sealer type. Then check the label on your actual product — coverage rates vary significantly by brand, formulation, and surface porosity. Rough or porous concrete absorbs substantially more sealer than smooth, troweled concrete. If your product lists a range (e.g., 200–250 sq ft/gal), enter the lower number — you'll use more, not less, on a real surface.
Set the number of coats and waste factor.
Most sealers require 2 coats for proper protection and uniform sheen. A single coat on new concrete is almost always inadequate. Keep the waste factor at 10% minimum — sealer is lost in the sprayer, roller nap, overspray, and spills. On highly porous or textured surfaces, bump it to 15–20%.
Read the container count and buy accordingly.
The calculator shows how many 1-gallon containers and 5-gallon pails to buy, plus an optimal mix of sizes to minimize waste. Buying in 5-gallon pails costs significantly less per gallon than single-gallon containers on most brands. Always buy slightly more than you need — sealer from a different lot number can vary in color and sheen, making it impossible to blend seamlessly on a touch-up.
⚠ Pro Tip: The coverage rate on the label assumes ideal conditions on a smooth, non-porous surface. On rough-broom-finished concrete or any surface that hasn't been sealed before, expect to use 20–40% more than the label says. First-time applications on raw concrete are always consumption-heavy. Run the calculator at the label rate, then add 15–20% on top of whatever waste factor you already applied.
Concrete Sealer Coverage Formula
The calculation is straightforward but where most people go wrong is using the optimistic (high) end of the label's coverage range, not accounting for multiple coats, and skipping the waste factor entirely. Here's the correct step-by-step process:
All figures include 2 coats and 10% waste. Actual usage varies with surface porosity and application method.
Which Concrete Sealer Type Do You Need?
Choosing the wrong sealer type is more expensive than ordering too little — you may have to strip and redo the whole surface. The right sealer depends on your use case, exposure, and whether you want a visible surface finish or an invisible protectant.
Concrete sealer selection guide by application, finish, durability, and typical coverage rate.
Sealer Type
Best For
Finish
Coverage Rate
Recoat Interval
Penetrating / Silane-Siloxane
Driveways, pool decks, exterior exposed to freeze-thaw
High-traffic commercial floors, areas needing abrasion resistance
High gloss or matte
350–450 sq ft/gal
3–7 years
Never apply a film-forming sealer (acrylic, epoxy, polyurethane) over a penetrating sealer — the film won't bond. Likewise, don't apply a water-based product over a solvent-based sealer without testing adhesion first. Strip the old sealer completely if changing product categories.
Common Sealer Coverage Mistakes
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Using the label's best-case coverage rate.
Manufacturer coverage rates are measured on smooth, non-porous laboratory surfaces. Real concrete — especially broom-finished, exposed aggregate, or any surface older than 5 years — is significantly more absorbent. If the label says 400 sq ft/gal, plan for 300 on a rough exterior surface. Always test a small section first.
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Planning for one coat when two are required.
A single coat of most sealers does not provide adequate protection and will look patchy and uneven on most concrete surfaces. Nearly every sealer manufacturer recommends two coats as a minimum for driveways and floors. Budgeting for one coat means buying more on a return trip — often from a different lot number, which can cause sheen variation.
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Applying sealer to damp or freshly poured concrete.
New concrete must cure for a minimum of 28 days before sealing. Applying sealer too early traps moisture inside the slab, causing bubbling, delamination, and white haze — all of which require stripping and starting over. Surface moisture content should be below 4% for most film-forming sealers. Test with plastic sheeting taped flat for 24 hours — if condensation forms underneath, the surface is too wet.
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Applying the second coat before the first has cured.
Solvent-based acrylics need 2–4 hours between coats in warm weather. Water-based products need 4–8 hours minimum. Applying the second coat too soon traps solvents or water, causing bubbles, cloudiness, or adhesion failure. Humidity and temperature dramatically extend these windows — always check the specific product's data sheet, not just the label.
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Buying only 1-gallon containers when 5-gallon pails are available.
For any job over 3 gallons, buying 5-gallon pails is almost always more economical. The cost per gallon on a 5-gallon pail of most concrete sealers is 20–40% lower than buying five individual 1-gallon containers of the same product. Check availability at your supplier before ordering — some colors and specialty formulations only come in 1-gallon sizes.
Frequently Asked Questions
It depends on the sealer type and number of coats. At 2 coats with 10% waste: penetrating sealers (200 sq ft/gal) require about 11 gallons per 1,000 sq ft; solvent-based acrylic (300 sq ft/gal) requires about 7.3 gallons; water-based acrylic (350 sq ft/gal) requires about 6.3 gallons; and polyurethane (400 sq ft/gal) requires about 5.5 gallons. These figures assume a smooth, moderately porous surface. Add another 10–20% if your surface is rough-broom-finished or highly porous.
Dry times vary significantly by sealer type. Solvent-based acrylics are typically dry to touch in 1–2 hours and ready for a second coat in 2–4 hours. Water-based acrylics are dry to touch in 30–60 minutes but need 4–8 hours between coats. Epoxy coatings require 8–24 hours between coats and 72 hours before foot traffic. Penetrating sealers are typically invisible once dry (30–60 minutes) and don't require a second coat the same day. Always add extra time in high humidity or temperatures below 50°F — cool, damp conditions slow curing dramatically.
Both work, but they produce different results and have different waste factors. A pump-up garden sprayer or an airless sprayer is faster and gives more even coverage on large areas, but loses 10–15% to overspray and misting in any wind. A 3/8-inch nap roller applies more product to the surface with less waste, but is slower and can leave roller marks if you work too slowly on fast-drying products. For exterior driveways and patios, a sprayer followed by a roller to work in the sealer (the spray-and-backroll method) gives the best result and minimizes product waste.
Recoat intervals depend heavily on sealer type, traffic, and UV exposure. Acrylic sealers on driveways typically last 1–3 years. Penetrating sealers on outdoor surfaces last 3–5 years. Epoxy and polyurethane coatings on interior garage floors can last 5–10 years with proper maintenance. UV is the primary enemy of all film-forming sealers — south-facing driveways in sun-belt states will need more frequent resealing than shaded northern surfaces. The tell-tale sign it's time to reseal: water no longer beads on the surface and soaks in instead.
Penetrating sealers (silane, siloxane, or silane-siloxane blends) chemically react with the concrete and become part of the surface structure. They are invisible, don't change the surface appearance, and repel water and chloride intrusion from within the slab. They're ideal for exterior exposure, freeze-thaw environments, and any surface where you want to preserve the natural look. Film-forming sealers (acrylic, epoxy, polyurethane) sit on top of the concrete and create a protective barrier. They are visible, can be glossy or matte, and protect against surface abrasion and staining. They require reapplication when the film wears off and can trap moisture if applied incorrectly.
Most sealers require surface and air temperatures to be above 50°F (10°C) both during application and for at least 24 hours afterward. Applying sealer when temperatures are too low causes water-based sealers to coalesce improperly, resulting in a milky, hazy finish that won't cure correctly. Solvent-based sealers are slightly more forgiving in cold weather but still shouldn't be applied below 40°F. Never seal over frozen concrete — even if the surface looks dry, ice crystals can be present in the pores and will expand, causing the sealer to bubble and delaminate.
Surface prep is more important than the sealer itself — a properly prepared surface will hold sealer twice as long as an improperly cleaned one. For existing concrete: sweep thoroughly, remove oil stains with a degreaser, etch with muriatic acid diluted 1:10 with water (or use a concrete etching solution) if the surface is smooth or glazed, rinse thoroughly, and allow 24–48 hours to dry completely before applying sealer. For new concrete: wait the full 28-day cure period. Never seal over dusty, oily, or wet concrete — adhesion will fail within weeks.
White haze or cloudiness in concrete sealer is called blushing, and it almost always means moisture was present during or after application. The most common causes are: sealing concrete that wasn't fully dry, applying sealer in humid conditions (above 85% relative humidity), applying too thick a coat that trapped moisture underneath, or applying a second coat before the first was fully cured. Minor blushing on solvent-based acrylics can sometimes be resolved by applying a thin coat of the same sealer, which re-dissolves the cloudy layer. Severe blushing requires chemical stripping and starting over.
Yes — sealing is essentially mandatory for stamped and colored concrete. The sealer protects the integral color from UV fading, prevents surface scaling, and enhances the wet-look appearance that makes decorative concrete appealing in the first place. Stamped concrete without sealer typically begins to fade and show surface wear within one to two seasons. Use a solvent-based acrylic for the most pronounced wet look, or a water-based acrylic for lower sheen and easier re-application. Plan on resealing every 1–3 years depending on traffic and UV exposure.
Yes, but use a sealer specifically formulated for pavers or masonry, not a standard concrete floor sealer. Paver sealers need to accommodate the movement at the joints and the polymeric sand between pavers. Acrylic-based paver sealers are the most common choice and provide joint stabilization alongside UV and stain protection. Coverage rates for pavers are typically lower than for poured concrete — 150–250 sq ft/gal is common — because the irregular surface texture and absorptive joints consume significantly more product. Factor in an extra 15–25% over the labeled rate when estimating for pavers or permeable surfaces.
