23rd Feb 2026
Fill Power is the industry method used to classify the quality of down. It is a measure of the volume a specific weight of down occupies at a controlled temperature and pressure.
The higher the Fill Power, the better the down quality.
Anything with a Fill Power above 500 is good.
700 and above is excellent, producing a lightweight duvet with impressive loft, of “fluffiness”.
This is a very short video to show the machinery used to measure Fill Power in action:
