How to Shrink a Hat

Cotton or Polyester Hats

Spray the sides of the hat with cold water. Load a misting bottle full of cold water, then use it to dampen the outer portion of the hat. Spray the sides and back, but don't soak them. If your hat doesn't have a bill, also mist its front end. Soaking the hat increases the chances that the colors run. Use a little bit of water at a time and make sure the fabric isn't dripping wet. For a hat with a bill, such as a fitted baseball cap, leave the front panels above the bill dry. This helps the cap keep its shape.

Dry the hat with a hair dryer set to a high setting. Hold onto the cap with your other hand, rotating it as needed to reach the other sides. Point the dryer directly at the cap, but keep moving it back and forth to prevent the fabric from getting too hot. Stop when the cap feels dry to the touch. Concentrate the heat on the main portion of the hat rather than the brim. Most hats have an elastic band or sweatband in the brim, and heating it causes it to lose shape over time.

Repeat dampening and heating the cap a few times as needed. Test the hap first before treating it again. A form-fitting hat feels snug but not restrictive. If it still feels too big, try dampening it and drying it repeatedly to shrink it further. You may need to repeat the treatment 3 or 4 times before the hat reaches the size you need.

Soak the elastic band for 10 minutes if the hat still feels loose. Fill the sink with a little bit of water, enough to cover the band but not the rest of the hat. Use water as hot as you can get from the tap. Then, set the hat in the sink, making sure the elastic band or sweatband around the brim is submerged. Concentrate the water on the elastic band, since that is the part that determines the hat's fit. Avoid wrinkling the exterior portion of the cap.

Heat the hat for 5 minutes in an oven set at 300 °F (149 °C). Preheat the oven as you prepare the hat. Line a baking tray with paper towels, then set the hat on top of them. Once the oven heats up, move the tray into it. Be careful when putting a hat in the oven. Using a higher heat setting can cause the hat to melt. Also, if you don't use paper towels, the bottom part of the hat will scorch and turn an unpleasant brown color.

Place the hat in a dryer set for a maximum heat cycle. If the hat still feels a little loose, move it immediately from the oven to the dryer. Set the dryer to the hottest setting and the longest cycle available. Let the hat cool before wearing it again. Machine drying cycles are rough on clothing, so expect the hat to change shape a little. For instance, the back end of a fitted cap may get flattened a little so it no longer has a perfectly rounded shape.

Wear the hat as you normally would to shrink it naturally. Put the hat on after heat treating it. The more you wear it, the more it stretches and shrinks to fit your head. Exposing the hat to sunlight or hot water causes the fabric to shrink down to its natural size. Wearing the hat improves the fit even if you choose not to risk the oven or dryer. To speed up this process, try wearing the hat during a hot shower, for instance. Keep it on until it dries.

Felt or Straw Hats

Spray the hat with cold water. Moisten the fabric before attempting to reshape the hat. Fill a spray bottle, then lightly mist the exterior portion of the hat. Get the hat damp, but don't soak it. Make sure it isn't dripping moisture. Always spray above the brim. Dampening the brim may cause the elastic band inside of it to lose its shape. Avoid spraying the inside part of the hat.

Heat water in a teakettle to create a steam bath. Fill the teakettle with water, then set it on the stove. Turn the heat up to a high setting and wait for the water to boil. Make sure the kettle shoots out a steady supply of steam. If you don't have a kettle, find an alternative way to produce steam. Try heating a pot of water or taking the hat into a steamy bathroom. Alternatively, heat up an iron and hold it close to the hat. A lot of professional hat makers and sellers have specialty steam machines that help them shape hats. Look online for a hat steamer to purchase one of these machines. It is useful if you buy a lot of hats that need shaping.

Hold the hat above the steam and shape it as it dries. Keep the hat about 6 in (15 cm) from the end of the kettle, letting the steam hit it. Start with the brim and adjust it by turning it up slightly as it softens. Then, heat the middle part of the hat and gently push it inwards. Finish by turning the brim back down to its original shape. The heat softens the fibers, making them malleable. Shape the hat while it is still warm and slightly moist.

Dry out the hat and heat it to shape it again. Set the hat aside in a spot with good air circulation but not a lot of heat or direct sunlight. When the hat feels dry to the touch, test it out. If it is still a little loose, dampen it and steam it again. The hot steam will cause it to shrink a little each time. If the hat is close to the perfect size, keep trying. You may need to do this a few times before the hat reaches the size you need.

Spray the entire hat with cold water if it still feels loose. Fill the spray bottle again, but this time spray both the inner and outer portions of the hat. To prevent the brim from losing its shape, avoid spraying it. Dampen the rest of the hat without soaking it. Keep the brim dry to prevent it from curling and wrinkling.

Leave the hat in a hot car for up to 1 hour. The best time to shrink the hat is on a warm, sunny day. Set the hat on the car seat in direct sunlight. The hat will shrink as the water evaporates. Start testing the hat after 30 minutes to ensure it shrinks to the correct size. To prevent the hat from shrinking too much, check on it often. Avoid leaving it in the car for hours at a time. When you're done with it, take it out and let it cool in open air. If using a car isn't an option, find other heat sources, such as a heating vent or furnace in your home. Keep the hat nearby so it gets hot.

Hat Size Reducers

Measure the space between the hat and your head. Put the hat on to gauge how it fits against your head. To measure the gap, slide your fingers between the hat and your head. Get a rough estimate of how much space you need to fill to make the hat fit snugly against your head. For a more accurate measurement, have someone else use a tape measure while you wear the hat.

Trim hat size reducers with scissors to the length you need. Hat sizers are adhesive pads or tape used to fill excess space inside of a hat. Use a tape measure on the inner part of the hat to determine its circumference. Cut the sizer with a sharp pair of scissors to fit it on 1 side of the hat. You are able to place 4 sizers total inside of the hat, 1 for each side. Many places that sell hats have sizers available, including online shops. Sizers are inexpensive and disposable, so they're easy to find and valuable for shrinking a hat without damaging it. When using wider pieces of filler pads or tape, make them more manageable by cutting them in half. Reduce each strip to a length of about 6 in (15 cm)

Tuck the strips underneath the inner lining of the hat. Set the hat upside-down on a flat surface. Locate the sweatband around the inner portion of the hat's rim. Pull the lining back, then tuck the sizer in behind it. Almost all hats have easily-accessible liners. Adhere the sizer directly to the hat if yours doesn't have an accessible liner or sweatband.

Test the hat before attaching the adhesive to it. Put on the hat while the sizer is in it. If the hat fits well, pull out the sizer, peel off the adhesive backing, then stick it to the hat. Keep the sizer behind the inner lining, but stick it against the hat instead of the lining. Add more sizers as needed to the hat's other sides to bring it down to the proper size. Sticking the adhesive backing to the inner lining leads to unattractive wrinkles. Always attach sizers to the hat instead of the lining. Sizers are disposable, so peel them off when you no longer need them.