Online Clothing Shopping for Women – How to Find the Perfect Size & Fit

One of the most difficult things about online shopping for fashion is sizing and fit. It’s hard to know how an item will fit you when you can’t try it on – but that certainly doesn’t mean it’s impossible to find a great fit online! Just follow a few simple guidelines to help you achieve the best fit possible.

Manufacturer’s Size

Know your standard size charts. I know this might seem obvious, but the standard US Size Charts are actually more comprehensive and complex than you might think. In fact, a lot of women buy the incorrect size because they don’t know the subtle differences between size types, leading to an uncomfortable and unbecoming wardrobe.

In the U.S., we follow the following Size Charts:

Misses (or “Regular”) Sizes are the traditional and most widely used sizes by designers. Misses Sizes are always EVEN NUMBERS and are at intervals of 2. In general, Misses Sizes are:  0, 2 (XS), 4, 6 (S), 8, 10 (M) 12, 14 (L), 16 (XL), 18, 20 (XXL).

Numerical Size Letter Size
0 XS
2 XS
4 S
6 S
8 M
10 M
12 L
14 L
16 XL
18 XXL
20 XXL

Juniors Sizes follow generally the same principal, but are ODD NUMBERS at intervals of 2. In general, Juniors Sizes are: 1 (XS), 3, 5 (S), 7, 9 (M), 11, 13 (L), 15 (XL), 17, 19 (XXL or 2XL). Juniors Sizes tend to be cut smaller and at different proportions to fit the dimensions of a teenage/young adult body (hence the name “juniors”) – so don’t assume a Juniors Size 13 is roughly equivalent to a Misses Size 12 or Juniors Medium is the same as a Misses Medium.

Numerical Size Letter Size
1 XS
3 S
5 S
7 M
9 M
11 L
13 L
15 XL
17 XXL/2XL
19 XXL/2XL


Petites Sizes follow the Misses Size chart, but include the letter “P” to denote they are a “Petite” Size (i.e. 12P, PXL). Petites are generally for women with a height of 5’4” and under. Petite Sizes are cut shorter and smaller by the manufacturer to accommodate women with smaller frames. This means a Petite Size will be shorter in length (inseam), sleeve length, pant rise, and torso length. Personally, I’ve also found that Petite Sizes tend to run smaller overall, so if I buy a Petite Size (I’m 5’4”), I’ll usually size up.

Short Sizes are also for women 5’4” and under, but unlike a Petite Size, Short Sizes are only shorter at the inseam or length – not cut smaller overall. This is a good option for a woman who is shorter but has a regular sized build.

Tall Sizes are indicated by a “Tall” or “T” next to the size label and are generally for women 5’9” or above. Tall Sizes are generally cut longer at the inseam (length), pant rise, torso and sleeve length.

Women’s Plus Sizes are for women with larger builds and are indicated by a “W” after the numerical size or by a numerical size followed by an X. Plus Sizes are: 0X or X (12W), 1X (14W/16W), 2X (18W/20W), 3X (22W, 24W), 4X (26W/28W), 5X (30W,32W). In general, most manufacturers don’t go beyond a 5X, but there are some specialty stores that can accommodate sizes over 5X.

Numerical Size Letter Size
12W OX or X
14W 1X
16W 1X
18W 2X
20W 2X
22W 3X
24W 3X
26W 4X
28W 4X
30W 5X
32W 5X


Plus Sizes are cut larger overall to accommodate a larger build – these sizes are generally made wider but not longer. Again, a Regular Size 12 and a Size 12W are NOT the same.

Women’s Plus Petite Sizes are for women who are 5’4” or under in height and have a larger frame. These sizes will usually have a “Woman Petite” or “WP” near the numerical size. This is generally a harder-to-find size type, but some well-known chain department and clothing stores do carry this size (Talbots is one brand that tends to have a nice selection).

High End Denim & Pants Sizes

Some higher-end brands label their jeans and pants differently than the Standard U.S. Size Chart above – such brands include 7 For All Mankind and Paige (these jeans usually retail for $150 and up). When shopping expensive denim brands, you might see the following sizes: 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33. In this case, the numerical size roughly corresponds to the waist measurement. For example, 7 For All Mankind lists a Size 23 as having a 22.25” waist measurement.

If you see a label that has two numeric sizes – such as 28/31 – this is the waist size followed by the inseam length.

If you’re trying to figure out how to convert these sizes to a standard size label, I’ve found the following guide helpful

Size Approx. Equivalent to… Letter Size
23 000 XXS
24 00 XXS
25 0 XS
26 1/2 S
27 3/4 S
28 5/6 M
29 7/8 M
30 9/10 L
31 11/12 L
32 13/14 XL


Again, this is a rough guide for fit and these brands tend to run small. Unless you’ve purchased one of these brand sizes previously and already know how it will fit, I’d recommend visiting the specific brands website for a fit guide before making a purchase online.

All Size 12s Are Not Created Equal

Although the manufacturer’s size label is probably the best indicator of fit, sizes do vary from brand to brand. While the above size labels are fairly industry standard, measurements for each size are not. Meaning one brand can say an XL fits a 40” Bust, while another brand lists an XL as a 39.5” Bust. In other words (and to make our lives even more complicated!), a Size 12 in one brand might be totally different from a Size 12 in another. For example, Old Navy sizes tend to run large, while Ralph Lauren sizes can run small. (In general, I’ve found that higher-end, expensive labels to run small. My rule of thumb is “the higher the price tag, the smaller the cut”.)

And Those Brands That Said “Forget this, I’m Doing My Own Thing”…

Additionally, there are some design labels that don’t follow the standard U.S. size chart at all, such as Chico’s or Torrid, and instead have their own numerical system. If you’re unfamiliar with these brands, it’s best to go to their website for sizing information before making an online purchase.

Vintage Sizes

Vintage Clothing is usually considered any item 20ish years or older. Clothing from the 90’s is now considered “vintage” (which I still can’t believe because I have many 90’s pieces I wore in High School still in my closet! Gap Slipdress with a choker anyone?) Clothing made before 1990 may bear a standard size, but is usually cut much smaller than a modern size. A size 10 vintage will probably fit like a size 6 today. This is because many brands have implemented “vanity sizing” – making the measurements larger that correspond to label sizes – to accommodate the modern world’s growing builds, while keeping consumers happy (hence the term “vanity”).

Know Your Measurements!

The best way to determine your size and if an item will fit you, is to know your measurements! There are two ways you can do this.

Measure Yourself…

First, start by using a measuring tape to measure your body. (This is best done with a partner who can help keep the tape from slipping, but it can be done by yourself if you prefer.) Keep a record of these measurements so you have them handy when shopping.

There are 4 main measurements you should know – Bust, Waist, Hips, and Inseam (Leg).

Bust – With your bra on (this is important because it will affect your measurement), use the measuring tape to measure around the fullest part of your bust. Keep the tape taught, but not tight.

Waist – Measure around the narrowest part of your waist – usually right near the bellybutton at your natural waist. Again, keep the tape taught, but not tight.

Hips – Standing in a neutral position with your feet slightly apart, measure around the fullest part of your hips.

Inseam – Measure the length of your leg from the upper thigh to heel.

You can also take additional measurements around the width of your thigh, arm width, arm length and shoulder width if desired, but usually these are not necessary unless you are buying an expensive, intricate item like a dress coat or fancy dress.

… And Then Your Clothing

In addition to the measurements of your body, you should also have measurements of a few pieces of your own clothing for reference. Choose 1 item from each category of clothing you own – i.e. jeans, sweater, dress, etc. (this should preferably be a favorite item that fits you perfectly) and measure the item.

For example, take a pair of your favorite jeans, lay them flat and unstretched, and measure the waist, hips, rise (this is the point from the crotch seam to the waistband) and inseam (the crotch seam to the hem). Make a note of these measurements and use as guide while shopping later.

Personally, I’ve found this to be the most effective means of gauging size while shopping online. I know my favorite Boot Cut Jeans skim my heel at a 30” inseam, but I prefer my skinny jeans to hit at the ankle at a 28” inseam. I prefer a Mid-Rise to my jeans at an 8-9” rise – and that after having a baby I should run screaming from any jeans with a low rise of 6” or shorter! The key is to be familiar with what works for you.

Check the Measurements Provided by the Seller

Most reputable re-sellers will provide you with measurements of the item. Read the sellers notes carefully so you know how the item is being measured. And take the measurements with a (small) grain of salt so-to-speak – retailers are not seamstresses or tailors, and therefore you should expect a small amount of human error in the measurements.

Style & Cut

Another thing to note when trying to find the perfect fit online is the style & cut of the item. Certain styles are specifically cut at larger/smaller sizes in order to follow the trend.

For example, skinny jeans are intended to be “skinny” – hence the name. So while you may fit perfectly into your Size 12 GAP boot cut jeans, you may not be able to breathe in their Size 12 skinny jeans. Again, check the measurements the seller has provided and look for any additional descriptors about fit. As a seller, I will usually note if an item is a “Relaxed Fit” or “Weekend Fit” (roomy, generously sized), Skinny, Slim Fit (Runs tight by design), and so on.


The final thing to consider when discussing fit is fabric. The item’s fabric will absolutely affect the fit! Items with stretchy fabric (such as spandex or nylon) will allow for more wiggle room, while some materials (like leather or silk) provide virtually no stretch. If an item is made from a more rigid fabric, it’s a good idea to anticipate that it may run snug.

When buying pre-owned, also remember that these items have been worn and washed. If an item has been laundered incorrectly, it may have shrunk in the wash. Particularly notorious fabrics for shrinkage are rayon, wool, alpaca, cashmere, and sometimes cotton. Most clothing re-sellers know their fabrics and cuts, and won’t touch an item that has been badly shrunk in the wash. But sometimes very minor shrinkages do occur in the laundry, so be sure to check both the measurements of an item and the condition description to ensure the item is not overly shrunk and/or stretched out by wash & wear.

Happy Shopping!

Thanks for checking out The GFab Guide Online Clothing Shopping for Women – How to Find the Perfect Size & Fit ! Don’t forget to check out our other Buying & Selling Guides. And, as always, Happy Shopping!