Quick Answer: How to Measure Grommet Top Curtains
Grommet top curtains, also known as eyelet curtains, are measured using the curtain rod length, not the window width.
This guide applies to custom made grommet top and eyelet curtains for homes, apartments, rental properties, accommodation, and selected commercial spaces.
Core formula:
Rod length × fullness = total flat curtain width
Fullness guide:
Grommet top curtains are usually made with approximately 1.8×–2.0× fullness.
The curtain drop is measured from the top of the curtain to the bottom hem. Because grommet top curtains have a fabric header above the rod, the visible length from the top of the rod to the bottom hem is usually around 3 cm shorter than the ordered curtain drop.
Our standard grommet rings have a 39 mm inner diameter and are generally suitable for curtain rods with a 26–30 mm outer diameter.
Drop adjustment within the standard product range does not affect pricing.
Key Measurement Rules
- Always measure from the curtain rod, not the window width
- Measure the usable rod length from bracket to bracket, excluding finials
- Curtain width is determined by fullness, not window size
- Flat curtain width is the exact manufacturing measurement
- Coverage width is an approximate installation reference only
- Grommet top curtains are designed for curtain rods, not curtain tracks
- The curtain sits slightly above the rod because of the eyelet header
- The visible curtain length from the top of the rod to the bottom hem is usually around 3 cm shorter than the ordered drop
- Allow more than 3 cm clearance between the top of the rod and the ceiling or cornice, as the curtain header sits above the rod
- Our standard grommet rings have a 39 mm inner diameter
- They are generally suitable for rods with a 26–30 mm outer diameter
- For the best match, the inner diameter of the grommet ring should usually be approximately 8–12 mm larger than the outer diameter of the curtain rod
- Other ring sizes or colours may be available upon request
- Drop does not affect pricing within standard range
Step 1: Position Your Curtain Rod
Correct rod placement helps improve the finished look, curtain movement, light control, and stacking space.
Height
Install the rod 10–15 cm above the window frame, or as close to the ceiling or cornice as possible for a taller and more elegant look.
For grommet top curtains, please allow more than 3 cm clearance between the top of the rod and the ceiling or cornice. This is important because the curtain fabric sits approximately 3 cm above the rod.
If the rod is installed too close to the ceiling or cornice, the curtain header may not have enough room to sit properly above the rod.
Width Extension
Extend the rod approximately 15–30 cm beyond each side of the window frame.
This helps provide:
- Better glass coverage when the curtains are closed
- More stacking space when the curtains are open
- Reduced side light gaps
- A fuller and more balanced finished appearance
Wall Clearance
Allow enough clearance between the rod and the wall so the eyelets and curtain folds can move smoothly.
Make sure the curtain will not catch on window frames, handles, blinds, or other fittings.
Step 2: Measure Rod Length
Measure the usable curtain rod length from bracket to bracket.
Do not include the finials at the ends of the rod, as curtains do not normally travel across this decorative area.
This rod length is the base measurement used to calculate the required curtain width.
Step 3: Check Rod and Grommet Ring Size
Before ordering grommet top curtains, check that your curtain rod is suitable for the eyelet ring size.
Our standard grommet rings have:
- Ring inner diameter: 39 mm
- Generally suitable rod outer diameter: 26–30 mm
For the best match, the inner diameter of the grommet ring should usually be approximately 8–12 mm larger than the outer diameter of the curtain rod.
This allows the curtain to move smoothly along the rod while keeping a neat and structured appearance.
Example:
- Rod outer diameter: 26–30 mm
- Recommended ring inner diameter: approximately 39 mm
If your curtain rod is much thicker or thinner than this, please contact us before ordering. Other ring sizes or colours may be available upon request.
Contact: care@homecurtains.com.au
Step 4: Choose Curtain Fullness
Grommet top curtains need extra fabric width to create natural folds when installed on the rod.
Recommended fullness:
- 1.8× fullness: softer, more relaxed folds
- 2.0× fullness: fuller, more balanced drape
For most homes, 1.8×–2.0× fullness gives a practical and attractive result for grommet top curtains.
Heavier fabrics may create deeper folds, while lighter fabrics may appear softer and more relaxed.
Step 5: Calculate Curtain Width
Core formula:
Rod length × fullness = total flat curtain width
Example:
- Rod length: 200 cm
- Fullness: 1.8×
- Total flat curtain width: 360 cm
This becomes:
- 1 set = 2 panels
- Each panel = 180 cm flat curtain width
The flat curtain width is the manufacturing measurement before the curtain is gathered onto the rod.
Step 6: Coverage Reference for Grommet Top Curtains
Each listed size on our website refers to 1 set of 2 panels.
Each set consists of:
- 2 panels
- Each panel measuring W… cm flat curtain width before gathering
For grommet top curtains, the approximate coverage width depends on the fullness you prefer.
At around 2.0× fullness, the approximate coverage width is close to the listed panel width of the set. At around 1.8× fullness, the same curtain set may cover slightly more width with softer folds.
Reference guide based on 1.8×–2.0× fullness:
- W120 cm per panel → approximately 120–133 cm coverage per set
- W150 cm per panel → approximately 150–167 cm coverage per set
- W180 cm per panel → approximately 180–200 cm coverage per set
- W200 cm per panel → approximately 200–222 cm coverage per set
- W250 cm per panel → approximately 250–278 cm coverage per set
- W300 cm per panel → approximately 300–333 cm coverage per set
Important Note
Coverage width is not exact and may vary depending on:
- Fabric type
- Fabric weight
- Rod diameter
- Preferred fullness
- How tightly or loosely the curtain is arranged on the rod
Coverage width should be used as a guide only. The flat curtain width is the exact manufacturing measurement used for production and pricing.
Step 7: Measure Curtain Drop
For grommet top curtains, the ordered curtain drop is measured from the top of the curtain to the bottom hem.
When installed, the curtain header normally sits approximately 3 cm above the rod. This means the visible length from the top of the rod to the bottom hem is usually around 3 cm shorter than the ordered curtain drop.
Recommended method:
- Measure from the top of the rod to your desired curtain finish point
- Add approximately 3 cm for the fabric header above the rod
- This gives the ordered curtain drop
Example:
- Top of rod to desired hem position: 240 cm
- Add header above rod: approximately 3 cm
- Recommended ordered drop: approximately 243 cm
Floor Finish Options
- Floating: 1–2 cm above floor
- Touching: lightly resting on floor
- Puddling: add approximately 5–10 cm extra length
Common Measurement Mistakes
Many people measure the window width and assume this determines curtain size.
Correct method:
Rod length × fullness = total flat curtain width
Another common mistake is measuring only from the top of the rod to the floor without allowing for the fabric header above the rod.
For grommet top curtains, remember that the ordered curtain drop is measured from the top of the curtain, not from the top of the rod.
A third common mistake is installing the rod too close to the ceiling or cornice. Grommet top curtains need more than 3 cm clearance above the rod so the fabric header has enough room.
Another common mistake is choosing a curtain rod that is not compatible with the grommet ring size. For smooth movement, the ring inner diameter should usually be around 8–12 mm larger than the rod outer diameter.
Need Help With Your Curtain Measurements?
If you are unsure, we can calculate your curtain requirements based on your rod length, rod diameter, preferred fullness, and desired curtain drop.
If you need a different grommet ring size or colour, please contact us before ordering.
Email: care@homecurtains.com.au
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