There are a few things you can look for when buying a duvet in order to ensure that you are purchasing a good quality product:
Fill Power: Fill power is a measure of how much space a certain amount of down or feathers will occupy. The higher the fill power, the better the quality of the down or feathers and the more insulation they provide. Look for duvets with fill power ratings of 600 or higher.
Fill Material: Duvets can be filled with down, feathers, or synthetic materials. Down is considered to be the best option because it provides the most insulation and is very lightweight. Feathers are less expensive than down but are heavier and not as warm. Synthetic fills are cheaper still, but they are not as warm as down or feathers and are not as durable.
Fabric: The fabric used to make the duvet cover is also important. Look for duvets made from high-quality cotton or silk, as these fabrics are soft, breathable, and durable. Avoid duvets made from synthetic materials as they are less breathable and may cause you to feel too hot or too cold while you sleep.
Stitching: Look for duvets with tight, even stitching, as this helps to prevent the fill from shifting and keeps the duvet evenly distributed.
Brand: Look for well-known brands with a good reputation for producing high-quality duvets. Reading customer reviews can also help you make an informed decision.