Which menstrual cup size is right for me?

- min read

Choosing the right menstrual cup size is like finding a shoe that fits perfectly. Before you buy a shoe you will find out your size and which shape fits you comfortably. The same rule applies to menstrual cups, although unfortunately, you can not just go into a store and try them until you find one that works well for you.

As every vagina is anatomically unique there is no such thing as 'one size fits all'. That's why we have a 120 day "no questions asked" money back guarantee. Try a Ruby Cup and if it does not fit, you can not change the size or get a full refund.  

Luckily, there are many different shapes and sizes of menstrual cups, which makes it possible for you to find the perfect fit.

Your "Goldilocks" cup, we recommend that you know your flow and your anatomy before choosing a menstrual cup.

Here are the two key factors to look out for when choosing the right size:

  • Heaviness of your menstrual flow
  • Position of your cervix

Once you know these two characteristics you can narrow down your pool of potential menstrual cups. Ruby Cup is a great starter cup and works well for the majority of users. If you're not sure about the height of your cervix, definitely read this guide .  

Ruby Cup is available in two sizes: small and medium. We recommend Ruby Cup Small If you have a medium to heavy flow and ruby ​​cup medium. These are the measurements of Ruby Cup:

Ruby Cup Small
For lighter to medium periods
Ruby Cup Medium
For medium to heavy periods
Cup length 46 mm 51 mm
Stem Length 19 mm 17 mm
Total Length 65 mm 68 mm
Diameter 40 mm 45 mm
Capacity to the rim 24 ml 34 ml
Capacity to the holes 19 ml 24 ml


If you have a low cervix Try Ruby Cup Small as it is shorter. So a good menstrual cup hack is to simply trim the stem if it's too long.

Still in doubt? Our recommendation

If you are still in doubt, remember that both cups work for you. Ruby Cup Small Because of your low cervix, you would just need to empty it more frequently.

Ruby Cup Medium, It's Greater Capacity Will Just Hold It Better Than The Ruby Cup.

If you have a low cervix, but want to use ruby ​​cup medium, you can just make it sit comfortably under your cervix.

We currently offer a Ruby Cup and a discounted rate. 

Do age or childbirth influence the menstrual cup size needed?

We do not recommend that you choose your menstrual cup based on whether you have given birth or not or your age. Since each body is anatomically unique, these are not very reliable factors. Ruby Cup Small instead of a Ruby Cup Medium and vice versa.

So keep in mind that giving birth does not mean that you now need a bigger menstrual cup. Your flow and cervix position are better indicators in our experience.

Further Reading

How To Decide
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How To Use a Menstrual Cup
You've tried tampons and pads, but you've heard about menstrual cups? Using Ruby Cup is very similar to using tampons...
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Traveling with a menstrual cup
Curious about how to use your menstrual cup in a busy public bathroom? It’s easy. Menstrual cups are a healthy and co...
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