A sun hat is a flat-bottomed crown with a wide brim, and you can make one in an afternoon with fabric, elastic, and a sewing machine
A basic sun hat has five pieces: a crown (the top part), a brim (the wide part that shades your face), a brim facing (the underside of the brim), and two pieces of elastic that hold it on your head. You do not need a pattern—you can draft one from measurements, or use a commercial pattern from a fabric store. The whole project takes three to five hours if you have sewn before, longer if you are new to a machine.
This guide walks you through cutting, assembling, and finishing a sun hat in cotton or linen. The method works for any head size and any brim width you want. You will need a sewing machine, thread, scissors, elastic, and fabric—nothing else.
Key Takeaways
- A sun hat has five pieces: a crown, a brim, a brim facing, and two elastic straps that attach at the sides.
- You can draft a pattern by measuring your head circumference and deciding how wide you want the brim, then drawing circles on paper.
- The crown and brim are sewn together first, then the facing is attached to the underside of the brim to hide the seams.
- Elastic straps are sewn into the side seams so they sit under your chin and keep the hat from blowing off.
- Topstitching around the brim edge gives the hat a finished look and keeps all the layers from shifting.
Measure your head and decide on brim width
Measure around your head where the hat will sit—usually about an inch above your ears and across your forehead. Write this number down; it is your head circumference. A typical adult head is 21 to 23 inches around.
Decide how wide you want the brim. A brim that extends 2 to 3 inches past your face is practical for sun protection. A wider brim (4 to 5 inches) is more dramatic. Write this down too—it is your brim width.
From these two numbers you can draft a pattern. The crown is a circle with a diameter equal to your head circumference divided by 3.14 (this gives you the radius, which you double). The brim is a larger circle with a diameter equal to the crown diameter plus twice your brim width. For example: if your head is 22 inches around, your crown circle is about 7 inches across. If you want a 3-inch brim, your brim circle is about 13 inches across.
Draft a pattern and cut your fabric
Draw your crown circle on paper using a compass or a bowl as a guide. Draw your brim circle the same way. Cut both circles out. These are your pattern pieces.
Lay your fabric on a flat surface. Pin the crown pattern to the fabric and cut around it. You need two crown pieces (one for the outside, one for the lining). Pin the brim pattern and cut one brim piece from your main fabric and one from your facing fabric (muslin, cotton, or a lighter weight of the same fabric works). You now have four pieces: two crowns, one brim, one brim facing.
Cut two pieces of elastic, each about 8 inches long. These will be your chin straps.
Sew the two crown pieces together
Place the two crown pieces with the right sides facing each other (the pretty sides touching). Pin around the edge. Sew around the circle with a seam allowance of half an inch, leaving a 3-inch opening so you can turn it right-side-out later.
Trim the seam allowance to a quarter inch all the way around. Clip small notches into the seam allowance around the curve—this helps the fabric lie flat when you turn it. Turn the crown right-side-out through the opening and press it flat with an iron. Fold the opening edges inward and pin them closed, then topstitch around the entire edge of the crown, which closes the opening and gives it a finished look.
Attach the crown to the brim
The crown sits on top of the brim like a dome. Fold the crown in half, then in half again, and mark the four fold points with a pin. Do the same with the brim. These marks help you space the crown evenly.
Place the crown on top of the brim with right sides together (the finished side of the crown facing down into the brim). Match the four pins. Pin all the way around, easing the crown to fit the brim—the crown is smaller, so you will gather the brim slightly as you pin. Sew around with a half-inch seam allowance.
Attach the brim facing and add elastic straps
The brim facing hides the seam where the crown meets the brim. Place the brim facing on top of the brim with right sides together. Pin around the outer edge of the brim. Before you sew, tuck the two elastic straps between the brim and facing at the side seams (where your ears would be), with the raw edges of the elastic pointing outward. The elastic should form a loop under your chin when the hat is on your head.
Sew the brim and facing together around the outer edge with a half-inch seam allowance, catching the elastic in the seam as you go. Trim the seam allowance to a quarter inch and clip notches around the curve. Turn the brim right-side-out so the facing is now on the underside, and press flat.
Topstitch the brim and finish the hat
Topstitching means sewing a visible line of stitches on the outside of the fabric. It holds all the layers together and gives the hat a polished look. Sew around the outer edge of the brim, about a quarter inch from the edge. Sew around the inner edge where the crown meets the brim too.
Try the hat on. The elastic should sit comfortably under your chin without pulling. If it is too tight, remove a few stitches and adjust the elastic. If it is too loose, tighten it. Once it fits, you are done.
Frequently Asked Questions
What fabric should I use?
Cotton, linen, or a cotton blend works well. Avoid stretchy fabrics like jersey. A weight of 4 to 6 ounces per square yard is ideal—heavy enough to hold its shape but light enough to fold without creasing permanently. Quilting cotton or home décor fabric are both good choices.
Can I make a sun hat without a sewing machine?
Yes, but it takes much longer. You can hand-sew with a backstitch, which is strong and even. Use a needle and thread, and sew slowly. Most people find a machine much faster, but hand-sewing works if you have the time.
What if my hat is too big or too small?
Measure your head again and recalculate the crown diameter. If the hat is too big, you can take in the side seams where the elastic is attached—remove a quarter inch on each side. If it is too small, let out the seams. You can also adjust the elastic length to make the hat sit higher or lower on your head.
How do I keep the brim from drooping?
Add a layer of interfacing to the brim before you sew it to the crown. Iron-on interfacing is easiest—fuse it to the wrong side of the brim fabric following the package directions. This stiffens the brim so it holds its shape.
Can I add a lining inside the crown?
Yes. Cut a third crown piece from a lightweight cotton or linen. After you sew the crown and brim together, sew this lining piece to the inside of the crown with right sides together, leaving a small opening. Turn it right-side-out and press, then hand-stitch the opening closed. This hides the seams and makes the hat more comfortable.