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Pillow Height Calculator
Stop guessing. Calculate exactly how thick your pillow needs to be to prevent morning neck pain.
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Why Pillow Height (Loft) Matters
Your head weighs about 10-12 pounds. When you sleep, your pillow's singular job is to support that weight at an exact height so your cervical spine (neck) remains perfectly aligned with your thoracic spine (upper back). If your pillow is too thick, your neck is painfully cranked upward. If it's too thin, your neck sinks down. Both scenarios cause morning stiffness, tension headaches, and migraines.
The Mathematics of Pillow Loft
- Side Sleepers: Require the highest loft. The pillow must fill the entire space between your ear and the edge of your shoulder.
- Back Sleepers: Require medium loft. The pillow only needs to support the natural C-curve of the neck.
- Stomach Sleepers: Require very low loft (or no pillow at all). A thick pillow will force your neck into severe extension.
How Your Mattress Affects Your Pillow
A firm mattress prevents your torso from sinking, meaning the distance between your head and the mattress is larger. A soft mattress allows your heavier torso to sink deeper into the bed, reducing the gap between your head and the mattress, which means you need a thinner pillow. Buying a single block of memory foam is dangerous because the factory has no idea how soft your mattress is.
Frequently Asked Questions
How high should my pillow be?
Side sleepers generally need a higher loft (5-7 inches), back sleepers need a medium loft (4-5 inches), and stomach sleepers need a very low loft (0-3 inches). Adjust this based on your mattress firmness.
Does an adjustable pillow actually work?
Yes. The human body varies drastically in shoulder width and weight. An adjustable pillow like the Siestly High-Rebound Memory Foam Pillow allows you to literally unzip the cover and add or remove handfuls of the Active-Core foam until you hit the precise alignment required for your spine.