Kite size comes down to two numbers — your weight and the knots — corrected by a third that few people state: how steady the wind is. Here is the starting table and the three things that actually move it.
| Rider weight | 12-16 kn | 16-20 kn | 20-25 kn | 25-30 kn |
|---|---|---|---|---|
| 55-65 kg | 10-11 m² | 8-9 m² | 7-8 m² | 5-6 m² |
| 65-80 kg | 11-12 m² | 9-10 m² | 8-9 m² | 6-7 m² |
| 80-95 kg | 12-14 m² | 10-12 m² | 9-10 m² | 7-8 m² |
| Above 95 kg | 13-15 m² | 12-13 m² | 10-11 m² | 8-9 m² |
For freeride twintips in full wind. A bigger board buys you a size down; strapless surf riding tends the other way.
The knots in the table are measured wind, not forecast. In this app a spot turns green for kite at 13 knots, and below 9 there is no point rigging: those are the same thresholds the alerts use, so when your spot lights up you already know which column you are in.
Compare mean and gusts before deciding: between 15 knots gusting 27 and a steady 18, the second day takes more kite and less nerve.
Two cover almost everything: one for the average wind at your spot and one about 3 m² smaller. A third only pays off if you often ride below 13 or above 28 knots.
No — on foil you drop a long way: the same day rides with 3-5 m² less, and the usable threshold falls to around 11 knots. These sizes are for twintips.