Window Replacement Cost Calculator
Replacing windows means budgeting for the window units, the installation labor for each, and a contingency for surprises such as damaged framing or trim repair. This calculator combines those into a per-window cost and a project total. Window and labor prices vary enormously by type, size, material, region and contractor, so every price here is a user-editable input you take from your own quotes. That keeps the estimate honest and specific to your project rather than relying on a misleading national average.
Window replacement cost formula
Cost per window = unit price + labor per window
Subtotal = cost per window x number of windows
Contingency amount = subtotal x (contingency / 100)
Total project cost = subtotal + contingency amount
This is straightforward arithmetic on your own quoted prices. The contingency is a percentage you set based on the age and condition of your home; older homes often warrant a higher figure.
Window replacement context
- Unit price varies by window type (double-hung, casement, bay) and material (vinyl, wood, fiberglass).
- Installation labor depends on access, the opening condition, and local labor rates.
- A contingency of 10 to 20 percent is a common planning allowance for surprises.
- Many jurisdictions require a permit; check your local building department.
- ENERGY STAR certified windows may reduce heating and cooling costs depending on climate.
Window replacement: frequently asked questions
How do I estimate window replacement cost?
Add the cost of each window unit to the installation labor per window, multiply by the number of windows, then add a contingency for unexpected work such as rotten frames or trim repair. This calculator does exactly that and gives a per-window and total figure. Use quotes from suppliers and installers for the unit and labor prices.
Why are the prices editable inputs?
Window prices and installation labor vary widely by window type, size, material, region and contractor. There is no single national figure that would be accurate for your project. To avoid presenting a misleading number, the calculator asks you to enter prices from your own quotes, so the result reflects your actual job.
What does the contingency cover?
A contingency is a percentage added to cover surprises found during the work, such as water-damaged framing, lead paint handling in older homes, or trim and drywall repair around the opening. A contingency of 10 to 20 percent is a common planning practice, but you should set it based on the condition and age of your home.
Should I include permits and disposal?
Yes, if they apply to your project. Many jurisdictions require a permit for window replacement, and removing old windows incurs disposal fees. Add these to the contingency or enter them within your labor figure. Check your local building department for permit requirements and fees.
Does replacing windows save energy?
Energy-efficient windows can reduce heating and cooling costs, and the U.S. ENERGY STAR program certifies qualifying products. The savings depend on your climate, the windows being replaced, and your energy prices, so treat any payback estimate as specific to your situation rather than a fixed national figure.
Official sources
- U.S. Department of Energy: Update or Replace Windows.
- U.S. EPA ENERGY STAR: Residential Windows, Doors and Skylights.
Reviewed by the CalculatorHub team, edited by James Graham, 16 June 2026. See our methodology.