About Fin Fun Monofin
Our monofin has a unique natural motion that looks like a real fin when swimming to create the illusion of an actual mermaid fluke! Made from high quality neoprene with an indestructible polypropylene insert, it is rigid enough to provide strong propulsion, but with flex to look like a real fin. And the carefully designed cuffs and foot pocket help hide feet and ankles.
The buoyancy of the neoprene cover compensates for the weight of the monofin, making it feel light in the water and allowing you to swim longer with less effort.
You have to feel it to believe it. Other monofins can hurt, pinch, or rub the feet and ankle. Our soft cuffs and neoprene are a pleasure to wear and easy to get on/off.
Not only does our monofin create a realistic mermaid look, the patented design propels you through the water quickly and efficiently, allowing you to swim up to two times as fast with less exertion! Watch a demonstration here.
Mermaid swimming is not just fun, it also provides great exercise! Helping you build muscles as you swim, our monofins are so comfortable to wear you can keep them on longer and strengthen our core muscle while you play.
OUR PATENTED DESIGN AND FUNCTION ENSURE WE HAVE THE BEST MERMAID MONOFIN ON THE MARKET.
THERE’S MAGIC INSIDE YOUR MONOFIN!
Our uniquely designed monofin was created to give your Fin Fun mermaid tail the most realistic look and movement possible. Shaped like a mermaid fin and covered in high performance neoprene, the custom molded insert is what makes the monofin hold its mermaid shape while providing the awesome propulsion experience of a fin.
The Fin Fun Monofin insert is made from a highly advanced polypropylene material blended with recycled plastics, which provides strength and rigidity while remaining extremely light and flexible. Using recycled materials also helps to reduce the plastic floating around our oceans!
Our premium monofin insert is extremely durable, but if it ever should break, Fin Fun offers a lifetime warranty on the insert so you can get a new one free!

MONOFIN FAQ
If you are buying a SWIMMABLE Fin Fun mermaid tail (any tail that is Youth size 6 or larger), you will need to use a monofin in order to swim like a mermaid in it. Without the monofin, you will just have loose fabric around your feet/ankles, and no way to propel yourself with your legs together in the tail. The monofin is what provides the propulsion to move you through the water as you use the dolphin kick movement, giving you the speed and grace of a real mermaid!
Our TODDLER mermaid tails do not use a monofin. These tails are more like a skirt with a fully open and loose bottom, which allows youngsters to move their legs in or out of water, so they can walk around on land and wade in pools.
If you already have a Fin Fun Mermaid tail and need just a monofin, you can order the monofin in the size you need right here.
When you are purchasing a new tail and monofin set together, choose your tail color and size here, and it will allow you to add the correct size monofin at the same time!
Keep in mind, you can always buy more beautiful tails to use with your existing monofin, since all are interchangeable. Click here to buy just a new mermaid tail all by itself.
Not at all! We have boys who love their merman tails, but many boys (and men) choose to swim in just the monofin without a tail, too. You can easily and comfortably wear a monofin without a full tail and still enjoy all the benefits of swimming in it, including the extra speed and the great workout! And for boys, adding one of our Shark Fins can transform them into a wild creature of the deep, swimming right alongside their mermaid kin!
Fin Fun Monofins are designed specifically to fit in Fin Fun mermaid tails. We recommend against using it with any other brand of tail for safety and performance reasons. Also avoid using another company’s monofin in a Fin Fun tail, as it can damage or destroy your mermaid tail in one use.
When purchasing your Fin Fun monofin, be sure you get the right size based on the size of your Fin Fun mermaid tail (not your foot size), or it may not fit properly. The foot sizing on both monofins is very broad thanks to the stretchy ankle cuffs and neoprene, and will fit almost any size foot. The Monofin Jr. fits into mermaid tail Youth sizes 6-10. For mermaid tails in Youth size 12 and all Adult sizes, you will need a Monofin Pro. When you buy a Mermaid Tail Set on our site, it will automatically include the correct Monofin based on the tail size you select.
Please note: Some other makers' mermaid tails are sewn closed at the bottom. We strongly advise customers never to use a mermaid tail that is not open at the bottom. Humans, especially children, need quick access to their feet when swimming.
The Jr is our smaller size monofin and fits all children’s shoe sizes and even some women’s shoe sizes.
The Pro is our larger size monofin that fits in our mermaid Size Youth 12, and all Adult size mermaid tails. This will fit all adult shoe sizes for both men and women.
ALL foot sizes might need to exert some effort to get your feet through the holes at first, but keep trying, there is plenty of room inside. The ankle cuffs are made to fit snugly so your monofin stays put while you swim, but your foot comes out easily when you want it to with just a slight tug and kick!
First of all, we do not recommend a monofin for any child under 6 years old, and do not make a monofin in a toddler size. They need their little legs and feet free as they learn how to swim. Toddler tails don't go past the feet, but these little mermaids still feel like the real thing!
For children age 6 and up (and adults), they must be a competent, experienced swimmer that meets the criteria we have outlined in our “Mermaid Ready” video and our safety materials that come with every tail.
Whenever anyone is trying a monofin for the first time, they should stay in shallow water until they are comfortable standing, floating and swimming in it! Also make sure to learn the Quick Release Method of removing the monofin before swimming in deeper water.
So, should you choose a monofin for your child? It really depends on your child’s swimming experience and ability, not their age. Once they meet our Mermaid Ready criteria, they should first learn to swim with a dolphin kick without anything on their legs or feet, then experience it with just the monofin, and then finally wear the tail with the monofin inserted. This can be learned very quickly and then they will be ready to have a great time, wowing everybody at the pool.
Adult supervision is always required for water safety. An adult needs to supervise carefully, making sure a child starts out in the shallow end of the pool. Start slow until you feel they are ready. Click here to read our full safety precautions and recommendations.