Thank you for purchasing our

Finally, a ruler that actually works!  Crystal, owner of Save The Milk has used her sizing methods to fit thousands of moms over the past several years for the correct breast pump flange.  She has rave reviews from her clients and how much she has changed their lives.  She has helped moms just like you reduce or eliminate their pain, increase their milk supply, and prolong their breast pumping journey.  After working with so many moms one on one using her proprietary methods, she wanted to be able to help more women than her time would allow, and so the Nipple Queen Ruler was born.  The perfect sizing tool to help you size yourself right from home!  But, finding the right size isn’t always the end of the road.  You may find that other issues arise, or that you still have questions.  We have compiled a list of faqs below to try and answer some of our most frequently asked questions. If you find that you are still needing more support, we offer the Pumping Pretty Breast Pumping Success System that will walk you through every step that Crystal works on with her one on one clients and gives you answers to all of your breast pumping questions, and access to a private Facebook group where Crystal is there to coach you and other moms in your same situation.  We wish you nothing but the best in pumping success!

Assembling the Nipple Queen Ruler™

Attach the measurement window by sliding it across the ruler.

Nipple Queen Ruler
Using the Nipple Queen Ruler™

1. Place your nipple in between the ruler slides as pictured.

2. Slide the ruler to the base of your nipple so that the curvature of your nipple aligns with the ruler.

3. Your nipple and the ruler should be lightly touching.

4. For standard pumps, the number marked on the ruler will be the flange size you’ll want to purchase (Spectra, Medela, Bellababy, Lansinoh, Avent, Motif, Babybuddha, etc.).

5. Please follow the guidelines on our Nipple Queen Ruler™ chart for the size flanges and/or inserts you may need for your specific pump.

Nipple Queen Ruler Instructions
Size chart

Elvie offers flanges in sizes 28mm, 24mm, & 21mm.  The Nipple Queen Ruler will provide your perfect size.  For sizes smaller than 24mm, you will need to purchase the 24mm Elvie flanges along with the inserts in smaller sizes.  You can use Pumping Pretty Inserts specifically designed for Elvie OG. More information on the Elvie pump can be found in our blog posts. 


Uses the same standard sizing as Spectra, Medela, Babybuddha, etc. listed on the size chart above.


Willow 1-3 Generation offers flanges in sizes 27mm, 24mm, & 21mm.  Typically, you will subtract 1-2mm from your measured size provided by the Nipple Queen Ruler. For sizes smaller than 21mm, you will need to purchase the 24mm Willow flanges along with inserts to be used specifically with Willow.  More information can be found about the Willow pump in our blog posts. This sizing excludes Willow Go. 


Uses the same standard sizing as Spectra, Medela, Babybuddha, etc. listed on the size chart above.

**Sizing for Willow Gen 1-3 becomes a bit harder as we compensate for their suction patterns. Please be aware that most moms will have a difficult time sizing for Willow but rest assured that you will likely have a better time using the Nipple Queen Ruler over the standard sizing Willow offers Please refer to our blogs for more detailed information.

Frequently Asked Questions

What should I know before purchasing a new size?

The perfect and best size is the one you respond to; the one that you are comfortable using, that allows you to empty and typically pump for 30 minutes or less. If you purchased the Nipple Queen Ruler™ you are likely experiencing difficulties pumping. Perhaps your nipples are bleeding, cracked, sore, blistering or you don’t feel empty after pumping for 30 minutes or more. These are all good reasons to size yourself. But if you find you are still having issues 48 hours or longer after sizing down, you will likely benefit by using the Pumping Pretty System, to which you will have immediate access.

When is the best time to measure?

The best time to measure will be just prior to your next pumping or nursing session when your nipples are the most natural.  If you pump every 2 hours, then you can measure before your next scheduled pump. By allowing time to pass before you measure, you allow swelling to reduce and you should get the most accurate readings for your new flange size with the Nipple Queen Ruler.

What if I have flat or inverted nipples?

Stimulate your nipples by massaging or pumping for two minutes until the ridges of your nipples appear. Then measure at the base of your nipple as shown in the illustration above. If you are still unclear about where the base of your nipple is you can typically see a change in color between your areola and nipple. The areola tends to be darker and as the nipple appears the nipple will be lighter.  At times you will see indentations of where your nipple and areola meet, that would be the location to measure from. Please see (here) for examples. You may benefit from using Pumping Pretty Inserts as they are designed to reduce air gaps when pumping. If you need more assistance with identifying your nipple type and what products would likely work best with them, the Pumping Pretty System may be your immediate solution.

What happens if I see a dip in supply?

It is quite normal to see a dip in supply after sizing down. In fact, it is the number one complaint I have heard from the moms I have sized over the years.  For this reason, I created The Switch Method.  This method is only needed if you are in fact experiencing a dip in supply, otherwise, just keep pumping with your new size.


The Switch Method:

Start a pumping session in your new size flanges.  Midway through your session, switch to your old size flanges.  This will adequately drain your breasts and train them to get used to the new size.  Continue this process for approximately 24-48 hours until the transition to the new size is complete. Typically after sleeping through the night and on your first-morning pump, you will find your supply is back to normal or better, only using the new size.


If you continue having a dip in supply you likely will need more assistance with sizing and determining why this is occurring. I recommend getting immediate access to Pumping Pretty System. 

What happens if I can't find a flange specific for my pump?

You have the option to interchange flanges.  Maymom & Medela 2-piece flanges are compatible with other 2-piece pumps that have narrow bottle-neck tops. For pumps like Bellababy, BabyBuddha & Motif Luna, you can use Maymom Spectra flanges as they are both wide-mouth bottle tops.  For BabyBuddha and BellaBaby you will just need to purchase Spectra backflow protectors in addition to the Maymom Spectra flanges.

You can also use inserts with flanges. I have listed the common brands here 

I thought your nipples aren't supposed to rub the flanges?

The perfect size flange for you will allow you to place your nipple perfectly centered in the flange, leaving a very small amount of room between your nipple and flange (approximately 2 mm of space).  Once you start to pump your nipple WILL rub the sides of the flange but this part is normal because if you look closely you will see your nipple is being pulled down the tube. If you find that transitioning to the new size is uncomfortable for the first few pumps, use lube, like lanolin to help you transition. Lower the suction a little until you get used to the size, typically 24 to 48 hours.

What are the signs that my flange is too big?

Many women start out with a flange that is too large with lots of room around the nipple.  If your nipple AND areola are being sucked into the flange, it is too big.  Your nipples may not get sucked down into the flange right away but after a few minutes, your nipple and areola will swell and double in size and may even touch the ends of the flanges.  

Farting and gulping sounds at first pumping can indicate your flange is too big.

Leaking from the bottom of the flange can indicate the flange is too big.

For a perfect fit, there should be approximately 2 mm between your nipple and the sides of the flange. Of course everyone’s fit will be different and if you find that you are more comfortable in a larger size, it is completely OK to use larger flanges.

What are the signs that my flange is too small?

Typically, I have found that most moms are in a size too big.  In the perfect sized flange, there should be approximately 2 mm of space between your nipple and the flange all the way around.  If you center your nipple in the flange and it barely fits or is rubbing the sides of the flange BEFORE you even begin pumping, you may be in a size too small. 

Can my nipples shrink?

It is quite common for your nipples to shrink after sizing down.  Prior to sizing down, It is likely that your nipples were sore and swollen from using the wrong size flanges.  Now that you’re pumping in the proper size, the swelling should go down, and therefore, you may notice your nipples shrinking.  You may also start to feel that old familiar pinching, rubbing, and discomfort.  If you notice this happening, we recommend using the Nipple Queen Ruler™ to resize yourself as there is a good possibility that you will need to size down once more.

What if I still just can’t get comfortable pumping and my output is still low?

I recommend upgrading to the Pumping Pretty System so you can get immediate access to answers to all of the common issues you may be facing. You will also be invited to our exclusive Pumping Pretty Facebook group where I will offer support, and you can connect with moms just like you.

Where can I buy my new flanges?

You can visit my Amazon shop to purchase your flanges, inserts, and other related products  (paid link).