calcs.homes
calcs.homes
Enter your flagpole's height and we'll suggest a well-proportioned flag size — too small looks lost, too large overwhelms the pole.
Estimate only — local etiquette and HOA rules may set their own size limits.
A common rule of thumb is a flag's fly (length) should be about a quarter of the flagpole's height. From there, the hoist (height) follows the US flag's standard 1:1.9 hoist-to-fly ratio. In the US, we round that to the nearest common retail flag size (3x5, 4x6, 5x8, and so on) since that's what's actually sold.
A 3x5 ft flag is the standard choice for a 20 ft residential pole, following the quarter-height rule of thumb.
The official US flag ratio is 1:1.9 (hoist to fly) — a 3 ft hoist pairs with a 5.7 ft fly, which retail sizing rounds to a clean 3x5.