Buy the right amount of paint. Every time.

Within about 10% if you measure carefully. The formula is well-established: paintable square footage divided by coverage per gallon, multiplied by number of coats. Buy 10% extra to handle touch-ups and inevitable spills.

Roughly 1.5–2 gallons for two coats on the walls alone. Add another half-gallon if you're also painting the ceiling, plus a quart of trim paint.

350 sq ft is the industry standard for smooth, primed walls. Drop to 250–300 sq ft for rough or porous surfaces, and 200 sq ft for heavy texture or popcorn ceilings.

Yes for new drywall, bare wood, big color changes (especially light over dark), or stained surfaces. Skip primer when repainting similar colors over previously painted walls.

Yes — gallon estimates, cost breakdown, and coaching are all free. Premium unlocks saved scenarios for multi-room projects, side-by-side estimates, and a printable PDF project plan.