How the numbers are calculated
Every figure is derived from your standing height using established anthropometric ratios —
the average proportions of the human body. The standing desk height tracks your
standing elbow height (about 62% of your height), because the golden rule of
desk ergonomics is that your forearms should be parallel to the floor with your elbows at
roughly 90°. The seated desk height uses your seated elbow height, the chair
height uses your popliteal height (the back of the knee), and monitor targets use
your eye height sitting and standing.
These ratios match the published height recommendations from the major sit/stand desk makers
to within about a centimetre across the 5’0″ to 6’4″ range. Treat the output as an
excellent starting point, then fine-tune by feel: shoulders relaxed, wrists straight, and the
top of the screen at or just below your eyeline.
Next steps
If your current desk can't hit these numbers, the fix is usually a
height-adjustable standing desk or a
monitor arm to bring the screen to eye level. A supportive
ergonomic chair locks in the seated posture.