What You Need

  • A metal tape measure (fabric measures stretch and give inaccurate results)
  • The curtain rod already installed (measure after installation, not the window frame)
  • A pencil and paper to record measurements

Step 1: Measure the Width

  1. 1

    Measure the length of the curtain rod

    Measure the usable length of the curtain rod — from one end bracket to the other (or from finial to finial, minus any decorative ends). This is the width your curtains need to cover.

  2. 2

    Calculate the fabric width needed

    Curtains should have more fabric than the rod width to hang in folds — this is called fullness. For a flat, modern look: 1.5x the rod width. For a light, casual look: 2x. For a luxurious, heavily gathered look: 2.5x. If your rod is 200cm wide and you want 2x fullness, you need 400cm of curtain width total. With two curtain panels, each would be 200cm wide.

Step 2: Measure the Drop (Length)

  1. 3

    Measure from the rod to your chosen endpoint

    Measure from the curtain rod (where the rings or hooks will sit) down to where you want the curtains to end: Sill length: to the window sill. Below sill: 10–15cm below the sill (works well for café-style rooms). Floor length: 1–2cm above the floor (clean, modern look). Pooling on the floor: 5–20cm longer than floor length (dramatic, romantic — requires more cleaning). Floor length is the most popular and forgiving choice.

  2. 4

    Add allowances to your drop measurement

    Add: 15cm for the bottom hem (folded under) and 5–8cm for the heading (top of curtain for the rod pocket or pinch pleat). So if your measured drop is 240cm, you need fabric that is approximately 260cm long before hemming.

Example Calculation

Rod width: 200cm. Fullness: 2x. Two panels needed. Panel width each: 200cm. Drop from rod to floor: 240cm. Add heading (6cm) and hem (15cm) = 261cm cut length per panel. Order: two panels each 200cm wide × 261cm long.

Ready-made curtainsIf buying ready-made (not custom) curtains, measure your window and choose the nearest standard size above your required dimensions — you can always hem them shorter, but you cannot make them longer. Standard sizes in Australia: widths of 140cm, 180cm, 225cm; drops of 183cm, 213cm, 243cm, 260cm, 290cm.

Frequently Asked Questions

Floor-length curtains that just graze the floor (1–2cm above) look the most polished and are the easiest to live with practically. Curtains that stop above the floor often look unfinished unless they are sill-length by design. Curtains that pool on the floor are beautiful but collect dust and are impractical in high-traffic areas.
For the best visual effect, hang the rod 15–20cm wider than the window frame on each side. This allows the curtains to stack back off the window when open, maximising light, and makes the window appear wider. The curtain fabric total width should be 2x the rod width for a full, lush look.