Most women don’t know why getting the right breast pump flange is so important & how to measure flange size. So if you are confused & frustrated from trying to understand your breast pump, let us guide you into the world of breast-pump fitting so you can discover all the answers you need.
What is a breast pump flange?
The Flange is the cone-shaped funnel that comes in contact with your body when placed onto the breast & nipple. It forms a seal between your breast & the plastic or silicon that creates a vacuum to extract milk.
Why Size matters
It is important to have the right Flange because if it doesn’t fit correctly, you experience nipple pain during or after the pumping.
In addition to breast & nipple pain, if you use wrong sized pump flange, it can also negatively impact the amount of milk you can get out of your breast.
- If the Flange fits too tightly, it increases the chance of milk ducts getting clogged or blocked.
- A Flange that fits too loosely won’t provide adequate suction. Of this, milk is also left in the breast & lower milk production in the future. As a result of this, Pain & infection can also develop.
How to find the right size of Breast Pump flange
To determine the best flange size, you will need to measure your nipple. For this, you can follow just four steps which discuss below:

- Click here and download the ruler.
- The page on an A4 at 100% scale, then measure the holes with a ruler.
- Fold along the dotted lines and cut out the grey circle that is closest to the size of your nipple.
- Stand in front of a mirror & measure your nipple through but remember, don’t include your areola.
So when you measure the size of the nipple, you can easily find the right flange size. But remember, Flange sizes should be 2-3 mm larger than nipple sizes. Our Flange inserts are available in two sizes: 24 and 27mm.
Once you have measured everything perfectly, you will be able to know if you have found the correct Flange once you place it on your breast.
A Flange fits correctly when:
- The nipple is centred in the tube
- No parts of your nipple rub against the side
- It is little or no areola pulled in when the pump is turned on
A flange is not fitting properly when
- If you experience nipple pain during or after pumping
- It seems that your nipple has become discoloured, chapped, or otherwise injured
Please, keep this in mind breasts are not identical. Each breast maye require a different size flange in some cases and it is normal. Flange size changes throughout your pumping journey. So it’s good before replacing pump parts, you remeasure flange size to confirm you are still using the correct size.