Choosing the perfect custom curtain is not just about style or color—getting the measurements right is everything. A curtain that’s too short, too narrow, or poorly fitted can ruin the look of a room and waste your budget. That’s why we created this no-fluff, beginner-friendly guide to measuring your windows like a pro.

Whether you're upgrading your living room or placing your first order from our Shopify store, here’s exactly how to get your window measurements right—the first time.

1. Step 1: Decide the Mount Type — Inside or Outside?

Before you even grab a tape measure, choose how you want your curtains to hang:

1.1 Inside Mount

• Curtains hang within the window frame

• Clean, built-in look

• Requires at least 2 inches of frame depth

• Great for Roman shades, blinds, or minimal designs

1.2 Outside Mount

• Curtains hang above or outside the window frame

• Helps make the window look larger and blocks more light

• More forgiving in measurement

• Ideal for blackout or dramatic floor-length styles

Quick Tip: Not sure which to pick? If your window has a shallow depth or you want better light control, go for outside mount.

2. Step 2: Measure the Width

2.1 For Inside Mount:

1. Measure the inside width of the window at three points—top, middle, and bottom.

2. Use the narrowest measurement.

3. Don’t deduct any space—the manufacturer (that’s us!) will do it for a perfect fit.

2.2 For Outside Mount:

1. Measure the full width of the window.

2. Add 4 to 8 inches on each side for better coverage and visual balance.

3. Example:

   • Window is 36" wide

   • Add 4" left + 4" right = 44" total curtain width

Hidden Tip: Wider curtains don’t just block more light—they help rooms look more luxurious.

3. Step 3: Measure the Height (a.k.a. Length or Drop)

3.1 For Inside Mount:

• Measure from the top inside edge of the window frame down to your desired endpoint:

  • To the sill

  • Below the sill (2–3 inches)

  • To the floor (leave ½–1 inch clearance)

3.2 For Outside Mount:

• Start measuring from where you want the curtain rod to sit—typically 4–6 inches above the window frame

• Decide how far you want the curtain to fall:

  • Just below sill

  • Floor-length

  • Or add 2–4 inches for a “puddle” effect (adds elegance)

Pro Tip: Always measure in three spots—left, center, and right—and use the longest to avoid crooked lines.

4. Step 4: Think About Fullness

Curtains should never look flat. You want them to have natural folds when closed. Here’s a quick guide:

• Example: For a 40" rod, order curtain panels that total 80"–120" in width.

Shopper Tip: If you love soft folds and dramatic drapes, go for more fullness.

5. Common Measurement Mistakes (And How to Avoid Them)

• Only measuring once — always measure three times

• Guessing curtain rod height — mark it first before measuring

• Ignoring furniture under the window — check for obstructions

• Not considering how the curtain hangs (grommets, hooks, rings) — this affects length

Final Thoughts

Measuring for custom curtains isn’t hard—you just need the right steps. By following this guide, you'll avoid costly mistakes and ensure a polished, designer-level finish for every window.Click here for more detailed measurement methods.

At uscurtains , we’re here to make custom simple. If you’re still unsure about your sizes, reach out to our support team — we’re happy to review your measurements before production begins.