Peak Expiratory Flow Calculator

This works out a predicted peak expiratory flow from height, age and sex using the Nunn and Gregg 1989 regression equations, the set behind EU scale EN 13826 meters. Enter the three figures and it returns the predicted flow in litres per minute and per second, and marks out the green, yellow and red bands at 80 and 50 per cent of the reference value. Give a personal best and the bands are measured from that instead, with the personal best shown as a percentage of predicted. Predicted values differ between published equations by a noticeable margin, so this is a reference point rather than a target, and the page gives no treatment advice.