Border Width: The Golden Ratio and Fibonacci Numbers How to Determine Border Widths

Figuring out the right border sizes isn't as hard as you might think!

Last week, we learned how to use the Golden Ratio to determine your sashing sizes. Use the same formula to find the best range of border sizes for your quilt or wall hanging. You can also use Fibonacci Numbers for multiple borders.

It boils down to what looks good and the size of quilt that you are making with a little bit of math thrown in.

Golden Ratio for Borders

As with sashing, the Golden Ratio for borders is 1.618 to 1 or 1 to .618. Start with the finished size of the most commonly used block in your quilt. If your block measures 15 inches wide (finished size), multiply that by .618 for a 9.25-inch border, then add quarter-inch seam allowances.

Multiple Borders

Using the Golden Ratio, if a border is 3” wide, the next border would be 3” x 1.618 = 4.854” wide (for ease in calculations, round it up to 5”). The next border after that would be 5″ x 1.618 = 8.09” wide (round it down to 8”). Calculations are pretty consistent with the Fibonacci numbers (3, 5, 8). 

Sherbet Dreams pattern from AccuQuilt

Fibonacci Numbers

1, 1, 2, 3, 5, 8, 13, etc.

Fibonacci Numbers are another, centuries-old, method for getting appealing results with border widths.

Add the widths of the first and second border together to get the width of the third. Add the second and third together to get the width of the fourth, etc. 

Any sequence of these numbers will result in borders that are pleasing to the eye. If you don’t want to bother with the math, Jinny Beyer created a genius caliper gauge that makes the task of determining multiple border sizes much easier.

How do you determine the widths of your borders?

Share this post...
Previous post Next post


  • sara knight - July 31, 2023

    Just the information I was looking for, thank you!

  • Bonnie Welsh - June 13, 2023

    Cati—So glad you found the information helpful. =)

  • Cati - June 13, 2023

    Thank you! This info is a definite game changer!

  • Debbie Henry - July 18, 2021

    You are welcome, Jackie. Thanks for reading!

  • Jackie Geisler - July 17, 2021

    Thank you for clearing the border width’s for me. Never new how to figure it out. Bless you for sharing your knowledge

  • Debbie Henry - July 16, 2021

    Glad it was helpful, thanks for reading, Marion!

  • Marion - July 13, 2021

    This is an easy and fast way to make your blocks.I wasted a lot of fabric because I don’t have enough to make any thing but this is GREAT!! Thankyou

Leave a comment