How Much Feather Fill Do I Need?
Calculating how much feather fill you need is easy. Simply measure your cushion, calculate its volume, and use our guide below to estimate the quantity of feather filling required.
Our 95% premium duck feather and 5% soft down blend is suitable for creating comfortable, supportive cushions. The quantity required will depend on your cushion dimensions and how firmly you want it filled.
Step 1: Measure Your Cushion
Measure the cushion's finished dimensions in centimetres (cm):
- Width: Side to side
- Length: Top to bottom or end to end
- Depth: Front to back when the cushion is filled
Step 2: Calculate the Cushion Volume
Multiply the width, length and depth together to calculate the cushion's volume in cubic centimetres. Divide the result by 1,000 to convert it to litres.
Volume Formula Width × Length × Depth ÷ 1,000 = Volume in litres
Example: A cushion measuring 66 cm wide × 43 cm long × 10.5 cm deep:
66 × 43 × 10.5 ÷ 1,000 = 29.8 litres
Step 3: Estimate the Required Fill Weight
Once you know the cushion's volume, multiply it by the estimated filling rate for your desired firmness.
| Filling Style | Estimated Fill Rate |
| Soft and relaxed | 100 g per litre |
| Medium firmness | 120 g per litre |
| Firm and plump | 150 g per litre |
Calculation:
Volume in litres × Fill rate in grams per litre ÷ 1,000 = Estimated fill weight in kilograms.
For example, a 29.8-litre cushion filled to medium firmness would require approximately:
29.8 × 120 ÷ 1,000 = 3.58 kg of feather fill
Step 4: Calculate the Total for Multiple Cushions
If you are filling more than one cushion, calculate the estimated weight for each cushion and add the results together.
We recommend allowing a little extra filling to accommodate differences in cushion construction and your preferred finished appearance.
Important Information
These calculations provide an initial estimate only. Actual filling requirements vary depending on feather size, fill power, cushion construction, fabric tension and the desired finished shape. The filling rates above should be confirmed against the specifications of the feather blend before being used as purchasing guidance.
For the most accurate estimate, use the dimensions of the finished cushion and consider whether you prefer a soft, relaxed appearance or a fuller, firmer result.