What is foam ILD?
Understanding Foam ILD: A Key Measure of Mattress Firmness
Foam ILD stands for Indentation Load Deflection and measures how much force is needed to compress foam. A higher ILD rating indicates a firmer foam, while a lower rating suggests a softer foam.
Foam used in mattresses generally ranges from about 16.5 ILD (plush) to 44+ ILD (extra-firm). However, ILD alone doesn’t fully determine mattress firmness. For instance, a thin piece of foam with a high ILD can feel softer than a thicker piece with a lower ILD. This variation occurs because ILD tests typically measure the force required to compress a 4-inch piece of foam by 1 inch, and thicker foams inherently provide more support.
For the most accurate assessment of comfort and firmness, it’s best to try the mattress in-store rather than relying solely on ILD ratings.
For more details on foam ILD, check out our blog:
https://www.nationalmattress.ca/blog/what-is-foam-ild