Curtain Size Calculator
Find the right curtain width and drop in minutes no guesswork. This curtain size calculator works in inches and centimeters, and shows rod length, finished panel length, fabric width, panel count, and more. It’s perfect if you’ve been searching for a curtains size calculator, a what size curtains do I need calculator, or a simple guide on how to calculate curtain size.
Use the tool: add window width/height, choose header style (eyelet/rod pocket/pinch-pleat), set fullness, and pick your stack-back. The calculator does the math.
How to calculate curtain size (quick guide)
Most sizing boils down to four decisions: rod length, fullness, panel width, and drop.
Formulas you’ll actually use
- Rod length
Rod length = Window width + (2 × stack-back per side)
Tip: Use 6–10 in (15–25 cm) stack-back per side, or ~10% per side on wide windows. - Fabric width needed
Fabric width = Rod length × Fullness (1.5×–2.5×) - Panels
Panels = Fabric width ÷ Panel width (≈52")→ round up. - Finished panel length (drop)
Measure from top of rod to floor and pick a finish:- Floor: ~1″ (2–3 cm) above floor
- Kiss: just touches the floor
- Break: +1–2″ (2–5 cm) on floor
- Puddle: +6–10″ (15–25 cm) on floor
Use the calculate curtain size tool above to run these automatically in inches & cm.
Pick the right fullness (by header style)
Fullness changes the look and coverage. As a rule:
- Eyelet / Grommet / Rod pocket: 1.5×–2×
- Pinch-pleat / Tracks: 2×–2.5×
Heavier or blackout fabrics look better at the higher end; sheers can sit a little lighter.
Curtain measurements in inches & centimeters (UK-friendly)
Prefer metric? Switch the calculator to CM for a curtain size calculator UK experience. You’ll see rod length, finished panel length, bracket positions, and panel counts in centimeters handy when comparing curtain size chart UK listings.
Step-by-step: how to measure curtains
- Measure window width inside the trim.
- Choose your mount: standard (4–6″ / 10–15 cm above trim) or near-ceiling (~2″ / 5 cm below the ceiling).
- Pick stack-back: 6–10″ (15–25 cm) per side (or ~10% each side for wider spans).
- Select fullness: based on header style (guidelines above).
- Measure drop: rod to floor; choose floor, kiss, break, or puddle.
- Check panel count: the calculator will suggest how many curtain panels you need.
Examples (reality-check your numbers)
Example 1: 60″ window (eyelet), 2× fullness, 8″ stack-back/side
- Rod length = 60 + 16 = 76″
- Fabric width = 76 × 2 = 152″
- Panels ≈ 152 ÷ 52 = 3 panels (round up)
Example 2: 180 cm window (pinch-pleat), 2.2× fullness, 18 cm stack-back/side
- Rod length = 180 + 36 = 216 cm
- Fabric width ≈ 216 × 2.2 = 475 cm
- Panels ≈ 475 ÷ 132 cm (52″) = 4 panels
Quick chart: typical ready-made sizes
(Use this as a sanity check your final numbers should come from the calculator.)
| Window Width (in) | Typical Panels (52″ each) | Suggested Rod (in) |
|---|---|---|
| 36–48 | 2 | 52–68 |
| 49–72 | 2–3 | 68–96 |
| 73–96 | 3–4 | 96–120 |
| 97–120 | 4 | 120–144 |
Metric note: 1 in = 2.54 cm.
Why this curtains size calculator is different
- Inches & CM: switch anytime; ideal for US and UK curtain measurements.
- Width + Drop together: functions as a curtain width calculator and curtain length/drop calculator.
- Style-aware: eyelet, rod pocket, pinch-pleat fullness recommendations included.
- Panel count clarity: know if you need 2, 3, or 4 panels before you buy.
- Rod guidance: suggested rod length and bracket placement to avoid sag on wider spans.
FAQs
What size curtains do I need?
Enter your window width, choose a stack-back (6–10″ / 15–25 cm) for each side, set fullness, and the curtain size calculator will return rod length, fabric width, and how many panels you need.
How to calculate curtain size for windows step by step?
Width inside trim → choose rod height → add stack-back each side → apply fullness → divide by panel width for panel count. The tool automates each step.
What fullness should I use?
Eyelet/Rod pocket usually 1.5×–2×; Pinch-pleat/Tracks 2×–2.5×. Go higher for blackout or heavy fabrics.
What size curtain rod do I need?
Use rod length = window width + 2 × stack-back. Over ~84″ (213 cm), plan on a center bracket and a sturdier rod.
How high should I hang the rod?
Standard: 4–6″ (10–15 cm) above the trim. For a taller look, near-ceiling with ~2″ (5 cm) gap.
Is this a curtain size calculator UK?
Yes, switch to CM for a UK-friendly workflow. It pairs well with any curtain size chart UK.
How many panels for a wide window?
After applying fullness, divide your fabric width needed by panel width (≈52″). Many wider spans end up at 3–4 panels.
Does the calculator cover curtain drop?
Yes. It outputs finished panel length for floor, kiss, break, or puddle styles.
Pro tips before you buy
- Near-ceiling mounting visually raises the room.
- A slight break hides uneven floors better than a hard “floor” finish.
- Sheers usually look best at 2× fullness; blackout at 2–2.5×.
- For bay or double windows, calculate each span or the total width plus generous stack-back.
Add the calculator to your cart (figuratively)
Scroll back to the Curtain Size Calculator. Switch between inches and centimeters, compare panel counts, and export or email your results so you can shop with confidence.