What size curtains for my window?
Measure the pole or track if you have one. If not, measure the window and add 40 cm.
Checked against UK retailer and maker guides on 21 October 2026.
Curtain width by window width
| Window width | Pole (window + 40 cm) | Dunelm 2× fullness: each curtain ≥ pole | Ideal Textiles 1.5× minimum: pair ≥ 1.5 × pole |
|---|---|---|---|
| 90 cm | 130 cm | 66 in (168 cm) | 46 in (117 cm) |
| 120 cm | 160 cm | 66 in (168 cm) | 66 in (168 cm) |
| 150 cm | 190 cm | 90 in (228 cm) | 66 in (168 cm) |
| 180 cm | 220 cm | 90 in (228 cm) | 66 in (168 cm) |
| 200 cm | 240 cm | Made to measure | 90 in (228 cm) |
| 240 cm | 280 cm | Made to measure | 90 in (228 cm) |
The rules behind it
- No pole yet: Dunelm says measure the window and add 40 cm (20 cm each side) for brackets, finials and the curtains stacked back off the glass.
- Full look: Dunelm’s “golden rule” is that each curtain panel is the width of the pole, which gives the pair about twice the pole width when closed. It calls this standard 2× fullness.
- Ideal Textiles: for a full, gathered look, a pair whose combined width is about 1.5 to 2 times the pole. The 1.5× column uses the low end of that range, so it gathers less than Dunelm’s 2×.
- Luxury: Dunelm’s luxury gather is 2.5 times the pole width.
Next, work out the drop (length).
Questions
What size curtains for a 150 cm window?
Add 40 cm for a 190 cm pole. For a full look, each curtain should be at least 190 cm, so a 90 inch (229 cm) width. At the low end of Ideal Textiles’ 1.5–2× range, 66 inch (168 cm) curtains give a pair of 336 cm, over 1.5 times the pole.
What size curtains for a 120 cm window?
Pole about 160 cm. 66 inch (168 cm) curtains give a full look.
Should curtains be wider than the window?
Yes. Dunelm suggests at least twice the window width across the pair for standard fullness.
Where these numbers come from
- Dunelm: how to measure for curtains
- Dunelm: how to measure for tracks and poles
- Ideal Textiles: curtain size chart
Checked 21 October 2026. Makers round sizes differently, so always check the dimensions on the product you're buying.