Flag Calculator | USA
Calculate official US flag dimensions and proportions based on federal specifications
Calculate Flag Dimensions
Official Colors
Standard Flag Sizes
Home Flag
3 × 5 ft
Garden Flag
12 × 18 in
Casket Flag
5 × 9.5 ft
Small Desktop
4 × 6 in
Large Display
6 × 10 ft
Stadium Flag
20 × 38 ft
Official Proportions
Flag Elements
Stripes
7 red and 6 white alternating stripes representing the 13 original colonies
Stars
50 white stars representing the 50 states, arranged in 9 rows
Union
Blue rectangle in upper left corner containing the stars
Flag History
Flag Etiquette
Display only during daylight unless properly illuminated
Raise quickly, lower slowly and ceremoniously
Never let the flag touch the ground
Fold in triangle with stars showing when storing
Retire worn flags with dignity through burning
Understanding US Flag Specifications
Official Standards
The US flag dimensions are governed by Title 4 of the United States Code, § 1 and § 2. These specifications ensure consistency across all official American flags, whether for government buildings, military use, or civilian display.
Proportional System
- •All dimensions are based on proportional ratios
- •Height-to-width ratio is always 10:19
- •Union occupies exactly 7/13 of the flag height
- •13 stripes of equal width span the full height
Star Arrangement
Common Uses
- •3×5 ft: Most common home flag size
- •5×9.5 ft: Military casket flags
- •20×38 ft: Large stadium displays
- •Custom sizes: Based on proportional ratios
Flag Design Formula
All flag dimensions are calculated using the proportional formula: Dimension = Ratio × Coefficient
- • Width: 1.9
- • Union height: 7/13 (≈0.5385)
- • Union width: 0.76
- • Stripe width: 1/13 (≈0.0769)
- • Diameter: 4/5 of stripe width
- • Vertical spacing: 1/10 of union height
- • Horizontal spacing: 1/12 of union width
- • Total: 50 stars in precise arrangement