When it comes to comfort and support, wearing the right bra size is just as important as choosing the right bra style. So how long has it been since you've checked your bra size? There are many factors in a woman's life that affect her bust measurements; for example, pregnancy and weight fluctuations. The average woman will wear six different bra sizes throughout her life. All things considered, it's probably worth your while to grab a tape measure and check your size.

We've looked at dozens of measuring systems and found that none of them are quite the same. And, careful testing has shown that none of them have 100% accuracy rate either. As much as we wish it were, measuring for a bra is not an exact science. So, what's a woman to do? Here is some common-sense advice for a perfect fit.

Start with this simple first step: If you own a bra that fits you perfectly, buy that size. How do you know it's a perfect fit? Here are some guidelines:

Band Size:

Make sure the band fits correctly. If the band is too tight and just plain uncomfortable, it's too small. Signs that your band size is too big include breasts falling out from the bottom of your bra, and the back riding up. A correctly sized band will fit firmly around your back, where most of the support is. The back and front of the band should be even and parallel to the floor.

The Band Test:

Try this little test with your bra hooked on the loosest setting: ask someone to put their hand between your back and the back of your bra, then to turn their hand 90 degrees. Their hand should now be very firmly wedged and they should not be able to pull the bra further away from your back.
A new bra should be able to pass this test with the clasp on the loosest fitting- this allows you to tighten the bra as it stretches with wear and washing. Never try a bra on its tightest fitting -- it should fit on its loosest.

Cup Size:

The cups should be large enough so that your breasts are encased and don't bulge out. If it is an underwire bra, make sure the underwires aren't poking breast tissue. It's best if the fabric panel between the cups sits firmly against your chest (sternum), although with some makes and styles, this won't be exact.

Now that you know how your bra should fit, we offer the following measuring guidelines. Keeping in mind the many variations in measuring systems, this is the closest we've come to an accurate way to measure for a bra. Our system is great for determining band size. Cup size is always the difficult calculation. Don't be surprised if the calculation results in the wrong cup size. You know your breast size better than any measuring system.

Finding Your Personal Bra Size

A bra size is made up of two measurement components: band size (i.e. 34, 36, 38) and cup size (i.e. A, B, C). To find your correct bra size, begin by wearing your best fitting bra - unpadded, and not a minimizer or sports bra (underwire doesn't matter). If possible, have someone other than yourself take the measurements. Not only is it faster, it also tends to be more accurate.

Cup Size

   1.  Standing straight, with your arms at your side, measure around your body at the fullest part of your bust. Wrap the tape measure around you so that it is just touching, but not binding. Note: Again, look in a mirror to assure the tape is parallel to the floor. Round up or down to the nearest inch as you did to find your band size.

   2.  Now, subtract your band size measurement from this second measurement. The difference is your cup size (see chart below).

Example: 38" - 34" (band size) = 4" = D cup size

Once you get into the D cup sizes and larger, there tends to be a discrepancy among brands as to what to call sizes beyond a D cup. We hope this chart, based on the manufacturers' sizing charts, clears up some of the mystery. Go ahead and measure as we described above and then refer below for your correct size in the various brands.

Fitting Comments

• For most women, one breast is larger. In many cases one breast may even be one cup size larger than the other. In such situations, you should choose the cup size that fits your larger breast.

• As the band size of a bra increases, so does the actual cup size of a bra. Therefore a D cup in a 38D is going to be smaller than a D cup in a 42D.

• If you have a small back, buy a bra that fits in the cups, then have your bra altered to remove the excess in the back.

• If you have a broad back, buy a bra that fits in the cups, then purchase an extender (see accessory section) to increase the size of the back of your bra.

Perfect Fit Checklist

Let's face it, do we really know what a good fitting bra looks like? What are the signs that a bra is the wrong size? Well, let us help. Here is a checklist of what to look for.

• Smooth fitting cups: If you don't fill out the cups, you need a smaller size. If you are "overflowing" in the cups, try a larger cup size or a style with a fuller cup design. The edges of the cups should also lie flat against your breast. If there is a gap (especially with padded bras), you should go down a cup size.

• Center panel lays flat against your breast bone: If it does not, this could be a sign that your cup size is too small, or the panel is not large enough to accommodate the separation between your breasts.

• The bottom of the bra in the front and back is parallel to the floor or slightly lower in the back: The lower edge of the band should anchor below the shoulder blades. The lower the back fits, the better the support.

• A finger can be run under the front band: Your bra should be snug, but not too tight. If it's tight, you need a larger band size or a looser hook placement.

• Still not the perfect fit? Consider an alteration. We alter our clothes for a better fit, why not a bra? One woman in our office really measures to a 35 band size. She therefore buys a 36D and has a dart put in at the sides.