Not sure which menstrual cup size is right for you?
Take our quiz to find your perfect Ruby Cup!
Everybody’s body is unique. So, when it comes to choosing the right menstrual cup size, we start the conversation with you, your body, and your periods.
This way, we can help you find out which menstrual cup size is best designed to meet your needs and manage your menstrual flow.
Choosing the right menstrual cup size can feel confusing at first. Your ideal size depends on factors like your cervix height, flow volume, and pelvic floor strength. Using our menstrual cup size chart and tips below will help you find a cup that is comfortable, leak-free, and perfect for your body.
You can also take the quiz mentioned above to find your cup size in just a couple of minutes.
Menstrual cup sizing: How big is a menstrual cup?
If you haven’t seen a menstrual cup before, at Ruby Cup we have two menstrual cup sizes – small and medium. And they’re made to fit every body.
Both cup sizes are made from soft, medical grade silicone and are designed to be easy to use and comfortable to wear.
Related Post: Got a Menstrual Cup That Doesn't Fit? Here's What You Can Do
Menstrual cup size chart
Compare the small and medium Ruby Cups with our menstrual cup size chart.
Ruby Cup’s menstrual cup measurements are:
- Small (our smallest menstrual cup) is 65mm high and 40mm wide.
- Medium (our largest menstrual cup) is 68mm high and 45 mm wide.
How to find the right menstrual cup size for you
When it comes to working out which of our soft cup sizes will work for you, we start by helping you find out how your body is actually shaped, both inside and out.
That’s because there are two factors to consider when you’re working out which size Ruby Cup will work for you.
1. How heavy is your menstrual flow?
The first thing to consider is how much blood you lose when you have your period. We call this your menstrual flow and it can be light or it can be heavy.
- Light flow? If you have a light menstrual flow, you may be using small or regular tampons and slim pantyliners or pads. You’re likely to be changing your period product a few times during the day.
- Heavy flow? If you have a heavy menstrual flow, you’re likely to be using super or super plus size tampons and maxi pads. You’re also likely to be changing your period product frequently during the day and also at night.
2. Do you have a low cervix or a high cervix?
- How to find your cervix: To find your cervix, you’ll need to slide your longest finger into your vagina. You can do this while you’re lying down, or with one leg up on the side of the bath or the toilet lid. You can also do this whether or not you have your period. We recommend that you wash your hands well first and try to relax. Then carefully slide your longest finger into your vagina.
- What does a cervix feel like? You’ll find your cervix sitting at the top of your vagina. It’s likely to be at the top of your front vaginal wall – closer to your belly button than to your spine. To the touch, it will feel like a smooth round, raised circle with a dimple in the middle – a bit like the tip of your nose.
- Do you have a high cervix? If your longest finger goes almost all the way into your vagina before it reaches your cervix you have a high cervix.
- Do you have a low cervix? If your longest finger finds your cervix around the middle knuckle mark, then you have a low cervix.
Menstrual cup size guide: What size menstrual cup do I need?
This simple guide will help you to match your menstrual flow and the position of your cervix to the size of Ruby Cup that will work for you.
Choose the right Ruby Cup menstrual cup for your cervix height and flow.
Not sure which menstrual cup size is right for you?
Troubleshooting common menstrual cup sizing issues
Even after choosing the right menstrual cup size, you might encounter some common challenges. Don’t worry, most issues can be solved with a few simple adjustments. Here are tips for troubleshooting and making your menstrual cup experience comfortable and leak-free.
1. Leaks
If your menstrual cup leaks, it may be due to an incorrect fit or positioning. Make sure your cup is fully opened and sits below your cervix, forming a proper seal. You can gently rotate the cup after insertion or run your finger around the base to check for folds. Choosing the correct menstrual cup size based on your flow and cervix height is key to preventing leaks.
2. Difficulty inserting or removing
Insertion or removal discomfort is often caused by muscle tension or incorrect folding techniques. Try different folding methods, such as the C-fold or punch-down fold, and relax your pelvic muscles during insertion. For removal, pinch the base of the cup to break the seal before pulling it out. Using a menstrual cup of the right size will make insertion and removal much easier. Check out our 'How to Insert a Menstrual Cup' guide for step-by-step instructions.
3. Discomfort or pinching
If your cup feels uncomfortable, it may be the wrong size or positioned too high or low. A small adjustment in placement can help. Some users find that trimming the stem slightly improves comfort, but always ensure you’re not compromising the cup’s seal. Remember, the correct menstrual cup size for your cervix height and flow can prevent most discomfort issues.
4. Cup sticking or not opening properly
Sometimes, the cup doesn’t fully open, causing discomfort or leaks. This can happen if the cup is too soft or the fold is not positioned correctly. Gently rotate the cup or run your finger along the rim to help it pop open. If this persists, check whether your menstrual cup size and firmness match your flow and pelvic floor strength.
5. Excessive movement
If the cup shifts or feels unstable, it might be too small. A larger cup can create a better seal and stay securely in place. Make sure the cup is fully unfolded and positioned according to your cervix height for optimal fit and protection.
By following these troubleshooting tips, most menstrual cup issues can be quickly resolved. If you’re still unsure about your fit, consider taking our menstrual cup size quiz to confirm the best size for you.
What if I order the wrong size?
We want you to experience the difference we know a menstrual cup makes, so we offer a no questions asked 120-day money-back guarantee.
“I have to say that I gave a lot of thought before switching to Ruby Cup from the conventional tampons and pads. I wasn’t sure about the physics of it and doubted about how comfortable I would feel. Such a waste of time! I love the product. I’ve only started using it, but I can easily say that it’s one of the best purchases I’ve made.” -Percem
Our 100% money-back guarantee not only gives you time to get used to using your new cup, but if you think you need to order a different size, we’ll exchange it for you, or give you your money back with pleasure.
“I bought a Ruby Cup three years ago and I'm never switching back to tampons. The first period with the cup getting it in and positioned right was a bit of a challenge but it's fairly easy to learn. By now I don't even have to think about it anymore. It works just as I hoped it would and I'm very happy with it.” -Marina
“I switched to a cup two years ago and can safely say I'm never going back! It's the best period-based decision I ever made! So easy to use and the freedom it gives is incredible.” -Alice
Periods are universal. Access to menstrual products and period care is not.
Ruby Cup was the first menstrual cup company to offer a built-in Buy One, Give One promise on every single cup that we sell. According to Plan UK, around 1 in 10 women globally have been unable to afford protection for their period at some stage in their lives.
When you buy a Ruby Cup, not only do you change your own experience of having your period every month – you can transform someone else’s experience too.
How does Buy One Give One work?
For every cup sold, Ruby Cup donates another to someone who doesn’t have access to period products.
To date, our customers have helped us to donate 100,000+ Ruby Cups and hold educational programs for women and girls in 13 countries across three continents, to help them manage their periods safely and effectively.
Today, over 200K people with periods around the world use a Ruby Cup – are you ready to join them?
