Yardstick Handicap (RYA Portsmouth Yardstick)

The Portsmouth Yardstick is a time-on-time handicapping system run by the Royal Yachting Association (RYA) that lets dinghies and small keelboats of different classes race together fairly. Each class holds a Portsmouth Number, a numerical handicap derived from recorded race returns; a faster boat carries a lower number. Corrected time equals elapsed time multiplied by 1000 and divided by the boat’s Portsmouth Number, so results compare across classes. The RYA publishes and revises the numbers annually from club race data. It is the standard UK club-racing handicap for mixed-fleet dinghy events.