Measure twice
Record slopes, openings, obstructions, and access.
Region detectedUnited StatesUSD · ft², ft, gal
Independent home project planning
Measure twice.
Buy once.
Practical calculators for material quantities and project budgets. Transparent formulas with US customary defaults, USD budgets, and an instant metric option.
✓ No signup✓ USD budgeting✓ US + metric units✓ Formulas shown
Find the right starting point
What are you planning?
Choose a common project or search the complete calculator and guide library.
8 calculatorsUS + metric unitsFree no signup
Estimate wall and ceiling paint, coats, and coverage.
or search by keyword
Eight focused tools
Choose your project.
Enter real measurements, switch between US and metric units, and see the assumptions behind every result.
Interior finishing
Paint Calculator
Estimate gallons for walls and ceilings.
Open calculator →FloorsFlooring Cost Calculator
Plan material, waste, and installation cost.
Open calculator →MasonryConcrete Slab Calculator
Convert slab dimensions into cubic yards.
Open calculator →Walls & ceilingsDrywall Calculator
Estimate sheets, screws, and joint compound.
Open calculator →RoofingRoofing Shingle Calculator
Estimate roof area, squares, and bundles.
Open calculator →Outdoor projectsFence Cost Calculator
Estimate panels, posts, concrete, and cost.
Open calculator →Outdoor projectsDeck Board Calculator
Estimate board count and linear footage.
Open calculator →RemodelingKitchen Remodel Cost Calculator
Build a line-item planning budget.
Open calculator →Advanced project planner
Planning more than one room?
Combine spaces, optimize package sizes, compare Good/Better/Best budgets, and save the result to My Projects.
Multiple roomsPackage optimizerBudget scenarios
Cost My Reno field library
Know what changes the number.
Original guides explain coverage, waste, safety, and scope—the decisions a calculator cannot make for you.
01Painting · 8 min
How Much Paint Do I Need? A Room-by-Room Guide
Measure walls, ceilings, trim, doors, and openings without buying far too much paint.
Read field guide →02Painting · 7 minPaint Coverage, Primer, and Number of Coats Explained
Understand why the same gallon covers different areas on different projects.
Read field guide →03Flooring · 8 minFlooring Waste Percentage: 5%, 10%, or 15%?
Choose a waste allowance based on material, layout, room shape, and installation pattern.
Read field guide →Useful numbers, honest limits
A documented baseline—not a purchase order.
Materials, site conditions, labor, code, delivery, and tax can change a real project. Cost My Reno shows its math so you can verify the inputs and compare quotes on equal terms.
Read our methodology →Verify the product
Check coverage, package quantities, and installation rules.
Check locally
Confirm permits, code, utilities, and licensed-trade requirements.