How Much Fabric Do I Need for Curtains? A Yardage Calculator for Every Window

Every drapery workroom has a story about the panel that came up four inches short. Usually it happened because someone measured the window instead of the rod, forgot the header allowance, or ignored a 27-inch pattern repeat until the second cut didn't line up. The good news: yardage isn't guesswork. It's six numbers and a little arithmetic, and once you've done it for one window you can do it for every window in the house.

Below is the exact method we use, a worked example you can copy, and a shortcut with wide-width fabric that can cut your yardage roughly in half.

Step 1: Measure the rod, not the window

Curtains are sized to the hardware, so install (or at least mark) your rod first.

Finished width. Measure the full length of the rod between the finials. Most rods should extend 4 to 10 inches past the window frame on each side. That extra space is your stackback, the spot where the drapes gather when they're open, so they don't block the glass. If your rod has returns (the bend back to the wall on a traverse rod or a wrap-around rod), add both return depths to the width.

Finished length. Measure from the top of the rod (or the ring eye, if you're using rings) down to where you want the hem to land:

• Float: half an inch above the floor. Clean, easy to vacuum, and the most forgiving if your floor isn't level.

• Kiss: just touching the floor. Elegant, but every eighth of an inch matters.

• Puddle: 2 to 6 inches longer than the floor. Romantic, but it collects dust and pet hair.

Measure in three spots across the width and use the shortest number. Old houses are rarely square.

Step 2: Choose your fullness

Fullness is the ratio of flat fabric width to finished width. It is the single biggest factor in how expensive (and how luxurious) your drapes look.

• 2x: standard for most pleated and grommet drapes. Looks tailored.

• 2.5x: our default for pinch pleats and ripplefold. Rich folds without feeling heavy.

• 3x: the norm for sheers. Lightweight fabric needs more volume to look intentional instead of skimpy.

Multiply your finished width by your fullness. That's the total fabric width you need across all panels.

Step 3: Count your widths

A width is one full selvage-to-selvage drop of fabric. Divide your total fabric width from Step 2 by the usable width of your fabric (usually the bolt width minus about 2 inches for selvages), then always round up to the next whole width. Split that number between your panels. If you end up with an odd number, cut one width in half lengthwise and give each panel a half.

Step 4: Calculate the cut length

Cut length is finished length plus everything that disappears into hems and headings:

• Bottom hem: 8 inches (a 4-inch double-fold hem, the workroom standard. It hangs better and gives you room to let down later).

• Header: 8 inches for a pinch pleat with 4-inch buckram, double-turned. A rod pocket needs pocket depth plus heading, times two. Grommets typically need 6 to 8 inches depending on the tape.

• Shrinkage/squaring: add 1 to 2 inches for natural fibers like linen and cotton. Polyester is stable, so you can skip it.

So a typical pinch-pleat panel is finished length + 16 inches.

Step 5: Account for the pattern repeat

Solids and textures with no visible repeat can skip this. For prints and woven patterns, every width has to match its neighbor at the seam, which means each cut must start at the same point in the pattern.

Divide your cut length by the vertical repeat, round up to a whole number, and multiply back. That's your new cut length. A 100-inch cut on a 27-inch repeat becomes 4 repeats, or 108 inches. Then add one extra repeat to the total order so you have room to position the motif where you want it (usually a full motif just below the header).

Step 6: Put it all together

Total yardage = (number of widths × cut length) ÷ 36

Add 5 to 10 percent as a safety margin for your first project. Cutting errors happen even to us.

Worked example: a 60-inch living room window

If that fabric had a 27-inch repeat, you'd be at 4 × 108 = 432 inches, plus one repeat, or roughly 12.75 yards. That's how a "simple" pair of drapes turns into a big fabric bill.

The wide-width shortcut: railroading

Here's what most DIY guides skip. Standard decorator fabric is 54 inches wide, which is why you're seaming widths together and buying length after length. Wide-width drapery fabric (118 inches or more) changes the math completely.

With wide-width goods, the bolt width becomes your drop. The fabric is railroaded: you turn it sideways so the 118 inches runs from floor to header, and you simply buy the total width you need in running yards. No seams, no matching, no stacking up widths.

Same window, wide-width fabric:

• Fabric needed across both panels: 180" + 12" for double 1.5" side hems = 192"

• 192 ÷ 36 = 5.33 → 5.5 yards

• Cut length (100") fits easily within a 118" bolt

That's 5.5 yards instead of 11.5, with no seams running down your panels. For anyone sewing more than one window, this is the single biggest saving you can make.

The one limit: your cut length has to fit within the usable bolt width. For a 118-inch fabric, that means finished drops up to about 100 to 102 inches with a pinch-pleat header. For two-story windows, you'll go back to standard orientation.

If you want to try this approach, a few of our wide-width drapery fabrics that sew up beautifully for a first railroaded project:

• Santiago Drapery Fabric: a 118" wide, easy-handling polyester in over 30 colorways. A great first project fabric.

• Pirlo Dimout Drapery Fabric: a 116" room-darkening weave for bedrooms and media rooms, without the stiffness of a blackout lining.

• Mona Drapery Fabric: double-faced, so it looks finished from the street side too. Handy for unlined panels.

Calculating yardage for sheers

Sheers follow the same steps with three adjustments.

1. Go fuller. Use 2.5x at minimum, 3x if you want that soft, cloud-like look.

2. Use a weighted hem if the fabric has one. Many wide-width sheers come with a weighted band (a small lead or polyester cord woven into the selvage). Used railroaded, that band becomes your finished bottom hem. You skip the bottom hem allowance entirely and just add the header. It's the cleanest hem you'll ever get on a sheer, and it hangs dead straight.

3. Be gentle at the side hems. A double 1-inch side hem is plenty. Bulky hems on sheer fabric show through.

For the same 72-inch rod at 3x fullness: 216" + 8" side hems = 224" ÷ 36 = 6.25 yards, with no bottom hem to sew.

A few weighted-band sheers worth looking at:

• Icon Sheer Fabric: 126" wide, soft and versatile, with a lot of neutral colorways for layering behind drapes.

• Carolina Sheer Fabric: 128" wide, which gives you extra drop for taller windows.

• Amara Sheer Fabric: a textured sheer with more presence on its own, when you want the sheer to be the star.

Quick-reference yardage chart

For pinch pleats, 84" finished length, 2.5x fullness, plain fabric:

These are planning numbers. Run your own measurements through the steps above before you order.

Before you place your order

A few habits that save money and headaches:

• Order everything at once. Dye lots vary from roll to roll. A second order three weeks later may not match your first panel.

• Get a swatch first. Hold it up in the actual window in the morning and evening. Color changes a lot with backlight, especially with sheers.

• Write your numbers down. Keep a simple card per window: rod width, finished length, fullness, widths, cut length, total. It makes reorders and future rooms painless.

Once you've done the math on one window, the rest go fast. And if you're sewing a whole house, wide-width fabric is worth a serious look. Fewer seams, less fabric, and a more professional finish. When you're ready to pick a fabric, browse our drapery and sheer fabrics by the yard, and if you're stuck on a measurement, send us your numbers. We'll happily double-check them before you cut.