Measuring & Installation

How to Measure Curtains Correctly for a Perfect Custom Fit

There’s nothing more frustrating than ordering curtains, hanging them up, and realizing they’re too short, too narrow, or just slightly off. The good news: getting it right is completely straightforward once you know what to measure and why. This guide covers everything — how to measure curtains for standard windows, large windows, sliding glass doors, French doors, and bay windows, plus how to figure out how high should curtains be hung and how wide should curtains be for a full, polished look. Step 1: Decide Where the Rod Will Go Before you measure anything, decide where you’re mounting the curtain rod. This single decision affects every other measurement. Here are your options: Just above the window frame (4–6 inches): The standard approach. Works well for most rooms. Halfway between the window frame and ceiling: Makes windows look taller and ceilings feel higher. A popular choice for living rooms and bedrooms. At ceiling height or crown molding: The most dramatic option. Creates a floor-to-ceiling effect even if your windows don’t reach the ceiling. This is the answer to how high should curtains be hung if you want maximum visual impact. For most rooms, hanging the rod as high as possible is the right call. It’s one of the easiest ways to make a room feel more expensive and spacious. Step 2: Measure the Rod Width The rod should extend beyond the window frame on each side so curtains can stack clear of the glass when open. Standard extension is 6–12 inches per side, meaning your rod is 12–24 inches wider than the window frame. For how to measure curtains for large windows, you may want to extend even further — up to 16 inches per side — so the curtains don’t block any light when open. Step 3: Calculate Curtain Width This is where most people underestimate. How wide should curtains be? Your total curtain width (all panels combined) should be 1.5 to 2.5 times the rod width for a full, gathered look. Skimping on width is the fastest way to make curtains look flat and cheap. For a casual, relaxed look: 1.5x rod width For a standard, full look: 2x rod width For a luxurious, heavily gathered look: 2.5x rod width Example: If your rod is 80 inches wide and you want a standard full look, you need 160 inches of total curtain width — typically four 40-inch panels, or two 80-inch panels. Step 4: Measure Curtain Length Measure from the top of the rod (or the bottom of the ring if using ring clips) down to your desired endpoint. How to choose curtain length depends on the look you want: Sill length: Bottom of curtain hits the windowsill. Rarely used in living rooms or bedrooms — tends to look dated. Apron length: 4–6 inches below the sill. Works in kitchens and casual spaces. Floor length: Curtain just grazes the floor (half an inch clearance). The most versatile and universally flattering option for living rooms and bedrooms. Puddle length: 2–6 inches extra on the floor. Luxurious and dramatic — best for formal spaces or high-ceiling rooms. For how to measure curtains for bedroom windows, floor length is almost always the right choice. For how to measure curtains for living room spaces, floor length or a slight puddle both work beautifully. How to Measure Curtains for Specific Window Types How to Measure Curtains for Large Windows Large windows need more panels to achieve proper fullness. Calculate your total curtain width at 2–2.5x the rod width, then divide by your panel width to determine how many panels you need. For very wide windows, consider using a center support bracket to prevent the rod from sagging. How to Measure Curtains for Sliding Glass Doors How to measure curtains for sliding glass doors: measure the full width of the door opening, then add 12–16 inches per side for stack-back. Your rod should extend well beyond the door frame so curtains stack completely clear of the glass when open. Length should reach the floor. How to Measure Curtains for French Doors French doors are typically measured per door panel. How to measure curtains for French doors: measure each door panel individually and choose curtains that mount directly to the door (with tension rods or door-mounted hardware) or hang above the door frame on a wall-mounted rod. If wall-mounted, the rod should be wide enough to clear both doors when open. How to Measure Curtains for Bay Windows How to measure curtains for bay windows: measure each section of the bay separately and treat each as an individual window. Use a flexible or angled curtain rod that follows the bay’s shape, or install separate rods for each section. Floor-length panels on each section create a cohesive, elegant look. How to Measure Roman Shades For an inside mount: measure the exact width and height of the window opening at three points (top, middle, bottom for width; left, center, right for height) and use the smallest measurement. For an outside mount: measure the area you want to cover, adding 2–3 inches on each side and 2–3 inches above the frame. How to Measure Custom Curtains Custom curtains are made to your exact specifications, so precision matters. How to measure custom curtains: follow all the steps above carefully, and when in doubt, measure twice. Most custom curtain makers ask for finished width and finished length — the dimensions of the completed panel, not the fabric before hemming. Always clarify this with your supplier before ordering. Are custom curtains worth it? For windows that aren’t standard sizes — very tall, very wide, or unusually shaped — custom curtains are almost always worth the investment. The difference in fit and finish compared to ready-made panels is immediately visible. FAQ: Measuring Curtains How high should curtains be hung for standard 8-foot ceilings? Mount the rod as close to the ceiling as possible — typically 1–2 inches below the ceiling or crown molding. This makes the ceiling feel higher and the window look larger. Avoid mounting the rod directly above the window frame; it makes the room feel smaller. How wide should curtains be for a 60-inch window? Your rod should extend 12–24 inches beyond the window (6–12 inches per side), making it roughly 72–84 inches wide. At 2x fullness, you need 144–168 inches of total curtain width — typically four panels of 36–42 inches each. How to measure curtains for living room vs bedroom? The measurement process is the same — rod width, curtain width (1.5–2.5x rod width), and length from rod to floor. The main difference is that how to measure bedroom curtains often involves blackout panels that need to overlap the window frame by at least 2–3 inches on each side to prevent light gaps. What’s the most common curtain measuring mistake? Ordering curtains that are too narrow. Always calculate total curtain width at a minimum of 1.5x the rod width. Flat, skimpy curtains are the most common reason a room looks unfinished even with expensive fabric. How to measure window treatments other than curtains? How to measure window treatments like zebra shades or roller blinds: for inside mount, use the exact window opening dimensions. For outside mount, add 2–3 inches on each side and 2–3 inches above the frame for full coverage and light blockage.