The Truth About Measuring for a Wig with a Cap: No More Guesswork

Get a perfect fit every time—even if you have a head full of hair or a bald dome.

Learn the correct way to measure your head for a wig while wearing a wig cap. Avoid common mistakes, get the right size, and make your wig look like it was made just for you.

A person wearing a flesh-toned wig cap, with a soft measuring tape wrapped around their head, looking in a mirror with a focused expression.
Close-up of hands holding a measuring tape around the back of a wig-capped head, showing the tape level and snug fit.
Close-up of hands measuring around back of head
A table with a wig cap, measuring tape, mirror, and pen and paper neatly arranged from above.
Flat lay of measuring tools

Introduction: Why Measuring with a Cap Matters

If you've ever bought a wig that felt too tight or, worse, kept slipping off, you know the frustration. The culprit? Measuring without a wig cap. A cap adds a thin layer of tension and changes the shape of your head slightly. Measuring bare-headed gives you a different result than measuring over the cap you'll actually wear. As a wig frame maker, I've seen hundreds of wigs ruined by bad measurements. Let's fix that.

What You'll Need

  • Soft measuring tape (not a metal one!)
  • A wig cap (preferably the same type you'll wear with the wig)
  • A mirror (or a friend with steady hands)
  • Pen and paper
  • Optional: a second measuring tape or string as backup

Step 1: Prep Your Hair and Cap

First, flatten your hair as you would under a wig. If you have long hair, braid it close to the scalp or pin it flat. Then put on your wig cap. Make sure it's snug but not painful—the cap should sit right behind your ears and at the nape of your neck. Adjust until it feels secure.

Step 2: Take Key Measurements

  • Circumference: wrap the tape around your head, over the cap, just above your ears and across the middle of your forehead. Keep it level.
  • Front to Nape: from your hairline at the forehead, over the top of your head, down to the nape of your neck.
  • Ear to Ear (over the top): from the front of one ear, over the crown, to the front of the other ear.
  • Ear to Ear (around the back): from the back of one ear, around the occipital bone, to the back of the other ear.
  • Temple to Temple: from one temple to the other, across the front hairline.

Step 3: Account for Cap Thickness

A wig cap isn't paper-thin. It adds about 0.5 to 1 centimeter of volume. When you measure over the cap, you naturally account for it. But if you're using a very thick cap (like a bamboo one), consider going up one size. I always tell my clients: 'Measure over the exact cap you'll wear, and if you'll switch caps, measure again.'

Common Mistakes

  • Measuring too tight: the tape should be snug, not digging in.
  • Measuring off-center: align the tape symmetrically.
  • Using a different cap: a thick winter cap and a thin lace cap give different results.
  • Ignoring your head shape: some people have flatter crowns or prominent occipital bones—adjust accordingly.

Tips for Different Cap Types

Lace front caps are thin, so you might need a slightly shorter front-to-nape measurement to avoid gaping. Monofilament caps often have adjustable straps, so be precise but don't panic—they offer a little wiggle room. Silicon-lined caps grip better, so you can measure slightly looser. When in doubt, consult the wig's size chart.

Conclusion: Perfect Fit Equals Confidence

A wig that fits perfectly doesn't shift during your morning commute or pinch after lunch. It stays put when you dance, and it feels like part of you. Taking the time to measure with a cap might seem fussy, but trust me—it's the secret to wig bliss. Now go grab your tape and get that perfect fit. Your wig will thank you.