Common U.S. window sizes run roughly 24–48 inches wide by 36–72 inches tall for hung styles, with nominal codes like 24×36 and 36×60 written as width × height.
For the full breakdown, see our best 14 Inch Window guide.
A 28×44 stamp on a window label means 28 inches wide by 44 inches high, and that order never flips. Replacement windows, though, are ordered from the opening size you measure — not the label — and the numbers on a chart are nominal, so the real unit in the wall can differ.
This chart breaks down the ranges by window type, then covers how to measure so you order the right unit the first time.
What Are The Common Window Sizes In Inches?
Nominal sizes cluster around a set of standard widths and heights that manufacturers build in volume. There is no single universal standard, so treat the numbers below as common ranges rather than guaranteed stock.
Frequent nominal widths are 24, 28, 32, 36, 40, 44, and 48 inches; frequent heights are 36, 44, 48, 52, 54, 60, 62, and 72 inches. Actual availability shifts by manufacturer, product line, and region.
Window Sizes By Type: Full Range Chart
Ranges differ materially depending on the window type, so a size that fits a double-hung opening may not exist for a casement. The table below lists common ranges by style.
| Window Type | Common Width Range | Common Height Range |
|---|---|---|
| Double-hung / single-hung | 24–48 in | 36–72 in |
| Casement | 18–36 in | 18–72 in |
| Sliding / horizontal | 36–84 in | 24–60 in |
| Picture | 24–96 in | 12–96 in |
| Awning | 18–72 in | 18–72 in |
| Bay / bow | 42 in and wider | 36–72 in |
Double-hung sizes use short codes: Pella lists examples such as 2030 (24×36), 2044 (24×52), and 2840 (28×48) in its size guide. Bay and bow windows are assembly products, usually built from multiple connected windows rather than a single unit, so simple width-and-height matching often falls short.
How Do You Measure A Window For Replacement?
Measure the opening in three places for width and three for height, then use the smallest figure — the most constrained dimension. Home Depot’s measurement guide directs exactly this: three width measurements and three height measurements, with the smallest taken as the ordering size.
Window labels state width first, then height in inches, so a code like 28×44 means 28 inches wide by 44 inches high, and that sequence stays fixed across brands. Verify the opening size before trusting any nominal code.
What Do The Size Codes And Numbers Actually Mean?
Nominal codes such as 2030, 2044, 2840, and 3050 correspond to inches, but the code itself is not the rough opening. The visible sash adds frame and jamb thickness, so the finished dimensions of the unit in the wall differ from the label.
A few common mistakes cause most ordering problems:
- Treating the nominal code as the exact finished dimension rather than a label.
- Assuming one universal standard covers every window type — ranges differ sharply by style.
- Taking one measurement instead of three width and three height checks.
Egress, basement, and bedroom applications may also be governed by local code, so a “standard” size can still be noncompliant for a specific room use. Check local requirements before ordering for those spaces.
Frequently Asked Questions
Do all window manufacturers use the same standard sizes?
No. Common ranges overlap, but each manufacturer, product line, and region sets its own available sizes. A 32×48 double-hung from one brand may not match another’s stock. Always confirm the exact size against the specific manufacturer’s specification sheet before ordering.
Is the window code the same as the rough opening?
No. Codes like 2840 are nominal labels, not rough-opening dimensions. The rough opening includes extra space for framing, shims, and insulation, so the two numbers rarely match. Order from your measured opening size, not from the code stamped on the label or shown in an old chart.
What is the most common window size in U.S. homes?
Nominal sizes near 24×36 and 36×60 show up frequently in the standard ranges for hung and picture windows. Frequent widths of 24, 28, 32, 36, 40, 44, and 48 inches pair with frequent heights of 36, 44, 48, 52, 54, 60, 62, and 72 inches, though availability varies by manufacturer and region.
References & Sources
- Pella. “Standard Window Sizes.” Supports nominal codes such as 2030, 2044, and 2840, plus width-then-height notation.
- Home Depot. “Window Measurement Guide.” Supports three width and three height measurements using the smallest dimension.
- PRL Glass. “Standard Window Sizes.” Supports common ranges by window type, including casement, sliding, picture, and awning.