Sailing Handicap Calculator (Portsmouth Yardstick)
Calculate corrected time for handicap sailing races using the Portsmouth Yardstick (PY) system.
Compare two boats to find the race winner on corrected time.
What is the Portsmouth Yardstick system?
The Portsmouth Yardstick (PY) is a handicap system used in dinghy and small keelboat racing to allow boats of different designs to race fairly against each other. Each class of boat is assigned a PY number — a numerical rating of its expected performance relative to a reference class.
A lower PY number means a faster boat. The reference PY is 1000, which by definition corresponds to the Laser dinghy in the UK system.
The corrected time formula
Corrected Time = (Elapsed Time × 1,000) ÷ PY Number
All competitors’ corrected times are compared — the boat with the lowest corrected time wins the race, regardless of who crossed the finish line first.
Example calculation
Boat A: Laser (PY 1100) finishes in 45 minutes. Corrected time = (45 × 1000) ÷ 1100 = 40.91 minutes.
Boat B: Topper (PY 1365) finishes in 52 minutes. Corrected time = (52 × 1000) ÷ 1365 = 38.10 minutes.
Boat B wins on corrected time despite finishing 7 minutes behind Boat A on the water.
Common Portsmouth Yardstick numbers (UK RYA)
| Class | PY Number |
|---|---|
| Laser Standard | 1100 |
| Laser Radial | 1147 |
| RS200 | 1046 |
| Topper | 1365 |
| Optimist | 1645 |
| Mirror | 1390 |
| Wayfarer | 1102 |
| Enterprise | 1122 |
Current PY numbers are published by the RYA and updated annually based on race results.