Paint Calculator: How Much Paint Do You Really Need?

Paint coverage isn't one-size-fits-all. It depends on the paint type and the surface you're painting. Here's the breakdown: - **Interior latex paint**: covers 350–400 sq ft per gallon. Typical is 375 sq ft. This is your go-to for living rooms, bedrooms, and hallways. - **Exterior latex paint**: covers 300–400 sq ft per gallon. Typical is 350 sq ft. Exterior surfaces are rougher, so they soak up more paint. - **Primer**: covers 300–350 sq ft per gallon. Typical is 325 sq ft. Primer is essential for bare drywall, stained walls, or drastic color changes. Most rooms have a standard height of 8.5 ft, but yours might be different. Measure from floor to ceiling – and don't forget to subtract windows and doors if you want a more precise number. The calculator above already accounts for a typical window and door, saving you the math. In my experience, people consistently underestimate how much paint they need by about 15%. That's why the calculator builds in a small buffer. You'd rather have a quart left over than run out mid-roll.

Use this table to get a rough idea before you even open the calculator. Remember, these are typical values – your actual mileage may vary depending on wall texture and color change.

Paint prices vary wildly. You can spend $15 a gallon for budget paint or $70 a gallon for premium. Most people land around $35 per gallon for a decent mid-range option. Here's the real-world math: a typical 12x15 ft room with 8.5 ft ceilings needs about 2 gallons of interior latex paint. At $35 per gallon, that's $70 for paint. Add a gallon of primer at $30, and you're at $100 for materials. Not bad for a room makeover. Honestly, this won't work if your walls are textured – textured surfaces can drink up 20% more paint. And if you're painting a dark color over light, you might need an extra coat. The calculator gives you a starting point, but trust your gut if the walls look thirsty. Use the calculator above to plug in your exact dimensions and get a personalized cost estimate. No ads, no fluff.

Before you head to the store, keep these tips in mind: 1. **Buy all paint at once**. Paint batches vary slightly in color. If you run out and buy another gallon, it might not match perfectly. 2. **Get primer for drastic changes**. Going from dark red to light beige? Primer saves you from doing three coats of expensive paint. 3. **Check the sheen**. Flat paint hides imperfections but is hard to clean. Eggshell or satin is better for high-traffic areas. 4. **Don't skip the calculator**. It's free, it's fast, and it saves you from that awkward trip back to the store.