Button spacing calculator
Enter the length of the opening, how many buttons you want and where the first and last go: the calculator spaces the rest evenly and lists every position from the top edge, in centimeters or inches.
From the top edge (neckline or collar seam) to the bottom edge.
To the center of the first button.
To the center of the last button.
For the buttonhole length.
Button positions
From the top edge
- Button 15/8 in from the top · 21 3/8 in from the bottom
- Button 24 in from the top · 18 in from the bottom
- Button 37 1/4 in from the top · 14 3/4 in from the bottom
- Button 410 5/8 in from the top · 11 3/8 in from the bottom
- Button 513 7/8 in from the top · 8 1/8 in from the bottom
- Button 617 1/4 in from the top · 4 3/4 in from the bottom
Check that one button falls at the fullest part of the bust so the opening does not gape; shift the offsets if needed.
Even button spacing is one division: spacing = (opening − top offset − bottom offset) ÷ (number of buttons − 1). For a 55 cm blouse opening with the first button 1.5 cm below the neckline, the last 12 cm above the hem and 6 buttons: (55 − 1.5 − 12) ÷ 5 = 8.3 cm between buttons. In inches: (22 − 5/8 − 4 3/4) ÷ 5 ≈ 3 3/8 in.
Where do the first and last buttons go?
- Top: close to the neckline or the collar seam, about the button's diameter plus a few millimeters below the edge, often 1.5 to 2 cm (5/8 to 3/4 in) to the center of the button.
- Bottom: on a shirt or blouse worn tucked in or open at the hem, the last button usually sits 10 to 15 cm (4 to 6 in) above the hem. On a dress, skirt or cardigan, place it a little above the hem or the end of the opening.
- Bust: a button at the fullest part of the bust stops the opening from gaping. Measure from the top edge to your bust line and check that one position falls there; if not, change the number of buttons or the offsets.
- Waist: on a belted dress, avoid a button right under the belt, where it makes a lump.
The positions are on the center front line. Mark them on the placket or button band with a removable marker or a pin.
How long should a buttonhole be?
A buttonhole is the button's diameter plus its thickness: about 3 mm (1/8 in) more than the diameter for a flat button, more for a domed or shank button. Make a test buttonhole on a scrap of the same fabric with the same interfacing: the button should pass through with a little push.
Vertical or horizontal buttonholes?
- Vertical buttonholes go on narrow plackets, such as shirt fronts, so the button stays centered on the band. Center them on the center front line, the top end slightly above the button position.
- Horizontal buttonholes hold better under strain: use them on waistbands, cuffs and coats. They start about 3 mm (1/8 in) past the center front toward the edge, so the button ends up on the center line when it pulls.
The overlap, from the center front to the edge of the opening, should be at least the button's diameter so the button never sits at the very edge. How to sew buttonholes and buttons covers marking, stitching and cutting them open.
Sewly's woven top with a button front marks the buttonholes on the pattern for you, spaced along the front at your size.
Frequently asked questions
How far apart should buttons be on a shirt?
Usually 7 to 10 cm (2 3/4 to 4 in) on shirts and blouses: closer on fitted garments and fine fabrics, wider on coats. Rather than choosing a distance, fix the first and last button and divide the space between them evenly.
Should buttonholes be vertical or horizontal?
Vertical on narrow plackets such as shirt fronts, horizontal where there is strain, such as waistbands, cuffs and coats. A horizontal buttonhole lets the button settle at its outer end, right on the center front line.
How long should a buttonhole be?
The button's diameter plus its thickness, about 3 mm (1/8 in) more than the diameter for a flat button. Test on a scrap of the same fabric and interfacing first.
How do I stop a blouse from gaping between buttons?
Put one button at the fullest part of the bust and space the others from it, or add a button. A small snap sewn between two buttons also keeps the opening closed.