Pillow height calculator: the loft range for your position and mattress

Calm Eden sleep deskUpdated September 2026Method published below. General information, not medical advice
Short answer

This calculator returns a range, not one number. For a 172 cm side sleeper on a medium mattress with 40 cm shoulders, the recommended compressed loft is about 11 to 13.5 cm (4.3 to 5.3 in). Back and front sleepers need less. No published standard defines an ideal pillow height, so verify the range in your own bed.

Pillow height depends on your shoulder, your mattress, how much your pillow compresses and which position you actually spend the night in. The published research disagrees with itself about what is optimal, which is why this page gives you a range and a test.

Work out your loft range

Four inputs, one range. The result is the compressed height you want under your head, not the height the pillow shows on the shelf.

Without shoes. 1 inch is 2.54 cm.
Across your back from shoulder tip to shoulder tip, arms relaxed. 36 to 46 cm covers most adults.

This is geometry and arithmetic, not medical advice. Persistent neck pain, or numbness in the arms, needs a clinician rather than a different pillow.

About this tool and its limits

Purpose: to support one decision, from numbers you supply.
Not suitable for: any medical, legal, safety or warranty decision.
Method type: arithmetic on your inputs, or an editorial rule stated below. It is not a validated model.
Accountable publisher: the editorial desk of this store.
Method version: 1.0. Last checked: 2026-09-14.

The calculation runs in your browser. This tool's own code does not save or transmit your answers. Separate site analytics and other services are described in our privacy policy.

Input What it means Accepted values
Your height (cm) Used directly in the calculation. any number, default 172
Shoulder width (cm) Used directly in the calculation. any number, default 40
Position you sleep in most Used directly in the calculation. On my side, On my back, On my front
Mattress firmness Used directly in the calculation. Soft (you sink in), Medium, Firm (you lie on top)

Worked example

With the pre-filled values shown above, it returns:

Headline result Side sleeping: 10.0 to 12.5 cm
Same range in inches 3.9 to 4.9 in
Centre of the range 11.0 cm compressed height
Where the centre comes from 172 cm height x position factor 1, plus the adjustments below
Mattress adjustment -1.2 cm for a soft mattress
Shoulder adjustment +0.6 cm for 40 cm shoulders

Calculation checks

Case Observed behaviour
Boundary input (highest accepted values) Front sleeping: 13.5 to 16.0 cm
Invalid input (zero values) Side sleeping: 10.0 to 12.5 cm

These checks show the tool behaves as documented. They do not establish medical or scientific validity.

What this result cannot tell you. It is an estimate derived entirely from the numbers you enter, using the relationships described on this page. It does not measure your situation, it does not account for anything not listed as an input, and it cannot establish which product you should buy. Where the result matters for your health, safety, money or a warranty, treat it as a starting point and check it against the primary source linked at the bottom of this page.

Products and commercial interest. This store sells the products these guides discuss. Product data never changes a calculation. To report a problem, use the contact page and include this page's URL, the inputs you used and the result you expected.

How the calculation works

  1. The base loft is your height in centimetres multiplied by 0.068, which gives about 11.7 cm at 172 cm. Height stands in for the whole set of body proportions, because head and neck measurements have not been shown to predict a comfortable pillow height.
  2. The base is multiplied by a position factor: 1.0 for side sleeping, 0.72 for back sleeping, 0.5 for front sleeping. Side sleeping needs the most, because the pillow fills the gap between the mattress and the side of the head.
  3. The mattress adjustment adds 1.2 cm for a firm mattress and subtracts 1.2 cm for a soft one. A soft mattress lets the shoulder sink, closing part of the gap and reducing the loft you need.
  4. The shoulder adjustment moves the result by 0.3 cm for every centimetre above or below a 38 cm reference, capped at 2 cm either way.
  5. The answer is a range 2.5 cm wide, rounded to the nearest half centimetre. You cannot resolve your own sleeping position to the millimetre, and you do not stay in one position anyway.
What the calculator does not knowIt cannot see how much your specific pillow compresses, how much your mattress has softened, or whether you sleep in the position you think you do. One study that tracked sleeping positions found people alternated between supine and lateral positions roughly 24 times a night (Cai, 2016). That is the strongest argument for testing a range instead of trusting one number.

The measurement procedure

Run this before you buy, and again after two weeks with a new pillow. It takes about three minutes and it overrules every chart, including this one.

  1. Lie on your own mattress, on your side, in the position you normally wake up in. Not on a shop floor and not on a display bed.
  2. Have someone look at your neck, or take a photo from the front at mattress level. The neck should sit roughly in line with the spine, not angled up towards a tall pillow or sagging towards a flat one.
  3. Slide your top hand, palm down, under the pillow at its deepest point. If your hand fits comfortably without lifting your head, the loft is close. If you have to push the pillow up, it is too low. If there is no gap, it is too high.
  4. Lie on your back and repeat. The pillow should support the curve of the neck and let the back of the head rest, without pushing the chin towards the chest.
  5. Repeat after ten minutes. Foam and down both compress under sustained load, so the height at minute one is not the height you sleep on. Judge over four nights, not one.
What you notice in the morning What it usually means What to change first
Neck stiffness or an ache at the base of the skull The head was held above or below neutral all night Move one step across the range in the direction that levels the neck
Numbness or tingling in an arm or hand Sustained pressure on the shoulder or forearm Check the pillow width and your arm position, and reduce the loft. If it persists, see a clinician
Headaches on waking Often neck position, sometimes grinding, dehydration or apnoea Fix the pillow for two weeks. If headaches continue, speak to a clinician
Waking hot, with a damp pillow Heat trapped by the fill and cover Change the fill or cover rather than the height
Pillow flat by morning The fill has lost its loft, not the wrong pillow Add fill, or replace the fill in an adjustable pillow

What published studies actually recommend

Study What it recommended
Kim et al., 2015, cervicothoracic spine segments 10 cm in the supine position, in 16 adults aged 20 to 30
Sacco et al., lateral position comfort 10 cm as the best comfort lying on the side
Li et al., supine comfort rating 7 cm as the most comfortable supine height
Tian et al., 2024, side sleepers on foam latex A medium individualised height, tested at 8, 10, 12 and 14 cm, performed best
Liu et al., 2016, head and neck biomechanics No universal, evidence-based guideline for pillow design or selection exists
Ergonomic review, 2021, ten studies from 1997 to 2021 Many hypotheses, no firm conclusions about optimal height in supine or lateral positions
The statement this page owes youNo published standard defines an ideal pillow height. There is no ISO figure, no clinical guideline and no agreed millimetre range. The studies above tested small numbers of healthy adults in controlled positions, using comfort ratings, pressure mats or modelling, and a review of ten studies concluded that firm conclusions are still missing for both the supine and the lateral position. Anyone quoting one ideal number, including a shop, is quoting a marketing decision rather than a standard. Two further findings matter: optimal pillow height has been found not to correlate with measurements of the head and neck, and users tend to rate softer pillows as more comfortable even when a firmer pillow holds the spine better. Judge on four nights, not on the first one.

Adjustable fill beats a perfect guess

If you fall between two range figures, or your shoulders sit outside the 36 to 46 cm band, an adjustable pillow removes most of the guesswork: add or remove fill until the procedure above says the neck is level, then keep the spare fill for the day the pillow compresses.

Compare the options

Questions people ask

Is a higher pillow always better for side sleeping?
No. Higher helps only up to the point where the neck is level with the spine. Past that, the head is pushed up and the neck is held in extension, and one study found that increasing pillow height raised pressure in both the cranial and cervical regions.
How do I know if my pillow is too high?
Three morning signs: a stiff neck or an ache at the base of the skull, a chin pointed towards the chest when you lie on your back, and a pillow that has not compressed by morning. The hand test in the measurement procedure settles it in about a minute.
Does the mattress firmness really change the pillow I need?
Yes, and it is the input most people leave out. A soft mattress lets your shoulder sink, which reduces the gap between the mattress and your head and so reduces the loft you need. Moving one pillow between a soft guest bed and a firm main bed can change the answer by a full centimetre.
How is pillow height measured?
Two ways, and only one matters. Shelf height is the pillow measured on a flat surface in a shop. Compressed height is what it measures with your head on it, usually about a third less. Measure compressed height, in your own bed, in your own position.
Can a pillow fix neck pain?
It can remove one daily cause of awkward neck position, and it cannot fix a disc, a joint or a nerve. Small studies on cervical pillows have produced mixed results, and one review criticised their quality and statistical power. If neck pain persists beyond two weeks, or comes with numbness in the arms, that is a clinician question.

Sources

  1. Liu SF, et al. Effect of pillow height on the biomechanics of the head-neck complex. PeerJ, 2016 — pmc.ncbi.nlm.nih.gov/articles/PMC5012320/
  2. Kim HC, et al. The effect of different pillow heights on the parameters of cervicothoracic spine segments. Korean Journal of Spine, 2015 — pmc.ncbi.nlm.nih.gov/articles/PMC4623167/
  3. Ergonomic consideration in pillow height determinants and evaluation: a review. Healthcare, 2021 — pmc.ncbi.nlm.nih.gov/articles/PMC8544534/
  4. Tian S, et al. The individualized optimal pillow height and neck support design for side sleepers. Medical and Biological Engineering and Computing, 2025 — pubmed.ncbi.nlm.nih.gov/39412632/
  5. Cai D, Chen HL. Ergonomic approach for pillow concept design. Applied Ergonomics, 2016 — pubmed.ncbi.nlm.nih.gov/26360205/

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