Epoxy Floor Coating Calculator — Gallons, Kits & Cost

    Calculate exactly how much epoxy, primer, and top coat you need to coat a garage floor or concrete surface. Get results in gallons, number of kits, and estimated cost based on your floor area. Free to use — no signup required.

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    How to Use

    1. Select your coating type — water-based is easiest for DIY; 100% solids and polyaspartic are more durable but harder to apply.
    2. Choose a garage size preset or enter custom dimensions.
    3. Select the number of base coats — one coat works for most water-based products; 100% solids epoxy often benefits from two.
    4. Choose a decorative flake coverage — light broadcast gives a speckled look, full broadcast hides the base color completely.
    5. Keep the top coat enabled for maximum durability and to lock in decorative flakes.
    6. Rate your floor condition — porous or cracked concrete absorbs more material.
    7. Optionally enter material costs.
    8. Hit Calculate for your complete material and cost estimate.

    Wondering what it costs to hire a pro? See our 2026 epoxy floor cost breakdown. New to epoxy? See our complete garage floor epoxy guide for step-by-step instructions.

    Quick Reference

    Epoxy coverage by type (per gallon, per coat, on good condition concrete).

    Coating TypeCoverage (sq ft/gal)CoatsPot LifeCure Time
    Water-Based Epoxy200 – 3001 – 22 hours24 – 72 hrs
    Solvent-Based Epoxy150 – 2501 – 21.5 hours24 – 48 hrs
    100% Solids Epoxy80 – 1201 – 230 min12 – 24 hrs
    Polyaspartic200 – 300115 min4 – 6 hrs

    Example Calculation

    A standard 2-car garage (20×20 feet = 400 sq ft) with water-based epoxy, light decorative flakes, and a top coat needs approximately 2 gallons of base coat, 40 lbs of flakes (2 boxes), and 3 gallons of top coat. With surface prep materials and supplies, total DIY cost runs about $200–$350. A comparable professional installation would cost $1,200–$4,800.

    Common Epoxy Costs

    MaterialTypical Price
    Water-based epoxy (per gallon)$30 – $50
    Solvent-based epoxy (per gallon)$40 – $55
    100% solids epoxy (per gallon)$45 – $150
    Polyaspartic coating (per gallon)$60 – $120
    Decorative flakes (25 lb box)$40 – $80
    DIY epoxy kit (1-car garage)$50 – $150
    DIY epoxy kit (2-car garage)$100 – $300
    Concrete etching solution (gallon)$10 – $15
    Professional install (per sq ft)$3 – $12

    Frequently Asked Questions

    How many gallons of epoxy do I need for a 2-car garage?

    For a standard 20×20 foot (400 sq ft) 2-car garage, you'll need about 2 gallons of water-based epoxy for one coat, or 4 gallons of 100% solids epoxy. Add 3 gallons of clear top coat if you're using one. Floor condition matters — porous concrete absorbs more product.

    What type of epoxy is best for a garage floor?

    100% solids epoxy is the most durable and longest-lasting (10–20 years), but it's the hardest to apply due to a very short pot life. Water-based epoxy is the easiest for DIY (2+ hour pot life) but may need recoating every 3–5 years. Polyaspartic coatings cure in hours, not days, but must be applied quickly.

    Do I need a top coat over epoxy?

    A clear top coat is strongly recommended. It protects the base coat from UV yellowing, adds chemical and abrasion resistance, and locks in decorative flakes. Without a top coat, your epoxy will wear faster and flakes may come loose over time.

    How do I prepare my garage floor for epoxy?

    Clean the floor thoroughly, repair any cracks or divots, then acid etch or mechanically grind the surface to create a profile for the epoxy to bond to. The moisture test is critical — tape a plastic sheet to the floor for 24 hours. If moisture appears underneath, you need a moisture barrier primer before coating.

    How long does epoxy garage flooring last?

    Water-based epoxy typically lasts 2–5 years. Solvent-based lasts 5–10 years. 100% solids epoxy and polyaspartic coatings can last 10–20 years with proper prep and a top coat. The biggest factor in longevity is surface preparation — poorly prepped floors cause 90% of epoxy failures.

    Is it cheaper to DIY or hire a professional?

    DIY epoxy coating a 2-car garage costs $200–$400 in materials. Professional installation runs $1,200–$6,000 for the same space, but includes diamond grinding, professional-grade materials, and a warranty. DIY is significantly cheaper but requires a full weekend of work and careful surface prep.

    Typical Results

    1-car garage(200 sq ft)1.0–1.5 gallons (per coat)
    2-car garage(400 sq ft)2.0–2.5 gallons (per coat)
    3-car garage(600 sq ft)3.0–4.0 gallons (per coat)

    💡 Acid-etch or grind the concrete before applying — epoxy won't bond to smooth or contaminated concrete.

    Common Mistakes

    • Applying epoxy when temperature is below 50°F or humidity is above 85% — it won't cure properly
    • Not testing for moisture vapor emission — high MVE causes delamination
    • Using water-based epoxy outdoors where UV exposure will cause chalking and yellowing