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Interior Paint Cost Calculator

Compare the cost of painting rooms yourself with hiring a pro, using editable paint and labor prices.

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Estimated cost

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Prep drives the painter's price

Two quotes for the same room can differ by 50 percent mostly because of prep: moving furniture, patching, caulking and masking. Doing that work yourself before the painter arrives, and saying so when you ask for quotes, is one of the easiest ways to lower a professional price without cutting quality.

How interior painting costs add up

Paint is the smaller part of an interior paint job. The calculator figures gallons as wall area × coats ÷ coverage, rounds up to whole gallons, and multiplies by your price per gallon. Mid-grade interior paint from the big-box stores runs about $30 to $50 a gallon in 2025-26, and premium lines cost more.

For a hired painter, the calculator multiplies wall area by a labor rate per square foot of wall and adds the materials. Angi's 2026 cost data puts painter labor at roughly $1 to $3.50 per sq ft, so $2.00 is a middle-of-the-road default for two coats on walls with light prep. Many painters bill materials at their cost or with a small markup, so the total here is a reasonable estimate rather than a quote.

DIY cost adds a one-time supplies budget for rollers, covers, brushes, tape, drop cloths, patching compound and a tray. If you already own good tools, lower that number. Primer adds about one gallon per 300 sq ft and is worth it on new drywall, patched areas, or dark-to-light color changes.

To get wall area, use the Paint Calculator on each room and add them up. Ceilings, trim, doors and heavy repair work are priced separately by most painters and are not included here.

Where these numbers come from

The formulas and default values in this calculator are based on:

  • Angi, Interior and Exterior Painting Costs (2026 data: labor about $1–$3.50 per sq ft
  • interior paint $20–$100+ per gallon by grade)
  • Sherwin-Williams and Benjamin Moore coverage of 350–400 sq ft per gallon

These are planning estimates. Check product labels, your local building code, and a licensed contractor before you buy materials or build.

Frequently asked questions

Is the labor rate per sq ft of wall or per sq ft of floor?

This calculator uses wall area, which is how painters measure the work. Cost guides that quote a price per square foot of floor space are describing the whole house, which is why those numbers look higher. If you only know floor area, multiply it by about 3 to 3.5 to estimate wall area for rooms with 8 ft ceilings.

Does a painter's price include paint?

Some quotes include paint and some list it separately; always ask. This calculator adds the paint cost to the labor so both options are compared on the same basis. If your painter gets a trade discount, lower the paint price to reflect it.

How can I lower the cost of a professional paint job?

Keep colors similar to the existing ones so one coat or fewer primer coats will do, bundle several rooms into one visit, and handle furniture moving and minor patching yourself. Scheduling in the slower winter months can also bring better pricing in many areas.

More Paint calculators

Paint Calculator Paint Coverage Calculator Exterior Paint Cost Calculator

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