How to Use US Flag Calculator
Choose whether you know the desired flag width or height, then enter that dimension in the unit you plan to use for drawing, cutting, printing, or fabrication. The calculator keeps the same unit throughout the result.
Use the scaled flag size to confirm the overall canvas, then use stripe height for the thirteen alternating red and white stripes. The union width and height define the blue canton area in the upper hoist corner.
For the star field, read the row pattern as alternating rows of six and five stars. The calculator does not draw every star for you; it gives the proportional construction values needed to lay out a clean design.
Formula & Theory - US Flag Calculator
The US Flag Calculator uses the standard 1.9 to 1 flag width-to-height ratio. If width is known, height = width divided by 1.9. If height is known, width = height multiplied by 1.9. Each stripe has height divided by 13.
The union height is 7 stripes tall, or 7/13 of the flag height. The union width is approximately 0.76 times the flag height, which is equivalent to 0.4 of the total fly width under the 1.9 ratio. The fifty stars are arranged in nine horizontal rows: six stars in the first row, five in the second, alternating until all fifty positions are accounted for.
Use Cases for US Flag Calculator
- Prepare a proportionally correct classroom or craft flag.
- Scale a print layout without manually recalculating stripe sizes.
- Check whether a custom sign, banner, or graphic keeps recognizable flag geometry.