Did your favorite baseball cap take a hit from a sunny hike or a long day outdoors? Sweat stains, dirt, and moisture buildup are common signs of wear and tear—but that doesn’t mean your cap is done for. Regular cleaning helps extend its life and keeps it looking sharp. In this guide, we’ll show you the best ways to clean a baseball cap—whether by hand, in the washing machine, or even in the dishwasher.
⚠️ Important: Before washing, always check the care label inside your cap. Not all baseball caps are washable—especially older ones that may contain cardboard in the brim, which can warp when wet.
Does My Baseball Cap Have Cardboard in the Brim?
Most modern baseball caps use a plastic insert to help maintain shape. However, vintage caps—especially from the 1980s or earlier—may contain cardboard. You can test by gently tapping or snapping the brim. A hollow, papery sound often means cardboard. If in doubt, stick to gentle hand-washing and avoid soaking the cap.
Best Ways to Wash a Baseball Cap
Whether you're dealing with heavy sweat stains or light surface dirt, these three cleaning methods can help. Use mild detergent and avoid hot water to preserve color and shape.
Hand Washing a Baseball Cap
Best for: All types of caps, especially delicate or vintage ones
Hand washing is the safest option—especially for dyed fabrics that may bleed. To test for colorfastness, rub a damp cloth with mild detergent on a hidden area. If the cloth picks up color, stick with hand-washing.
What You’ll Need:
- Mild laundry detergent
- A clean bowl or sink
- A soft-bristle brush (like a toothbrush)
- Clean, lukewarm water
Step-by-Step Instructions:
- Lightly dampen the cap or just the dirty areas.
- Mix water and detergent in a bowl. Dip the brush in and gently scrub the stained spots in circular motions.
- Rinse with clean water. Use a towel to blot excess moisture, then air dry the cap. Do not place in direct sunlight or use heat.
💡Tip: For stubborn sweat stains, check out our dedicated blog post on removing tough cap stains.
Machine Washing a Baseball Cap
Best for: Caps labeled as machine washable (check the care tag!)
Some baseball caps can safely go in the washing machine—but be cautious. Avoid this method for caps with cardboard brims, delicate stitching, or vintage materials.
Instructions:
- Set your washer to a gentle cycle, max 86°F (30°C).
- Use a low spin speed to prevent shape damage.
- Add a small amount of mild detergent to the wash compartment.
- Let the cap air dry naturally—never use a dryer or place it on a heater.
Dishwasher Method for Cleaning a Baseball Cap
Best for: Durable caps with no cardboard brim
Surprisingly, the dishwasher can be a safer alternative than a washing machine. There’s no aggressive spinning, which reduces the risk of misshaping the cap.
✅ Make sure:
- The dishwasher temperature does not exceed 104°F (40°C).
- No dirty dishes are in the wash cycle.
- You turn off the heated dry setting.
- The cap is supported (e.g., placed over a bowl) to retain its shape.
Instructions:
- Set the dishwasher to a gentle cycle at a maximum of 104°F (40°C) and disable heat drying.
- Use a gentle, bleach-free detergent or dishwasher tab.
- After the cycle ends, carefully remove the cap and let it air dry.
