Toilet Flapper Sizes

Bathroom Scape may collect a share of sales or other compensation from the links on this page. This comes at no additional cost to you, and all the prices and availability are accurate at the time of publishing.

There are many different types of toilet flappers available these days. And, with so many sizes and shapes, it can be difficult to know which one is right for your toilet. In this blog post, we will discuss the different sizes of toilet flappers and how to measure them as well as the different toilet flapper frames available. We will also explain what toilet flapper features to use to reduce your water bill.

 What Size Toilet Flapper Do I Need

Korky 100BP Ultra High Performance Flapper Fits Most Toilets - Long Lasting Rubber - Easy to Install - Made in USA, Small, Red

The type of toilet flapper is important, but it is also vital that you purchase a replacement that is the correct size.  In the past, all toilets used a universal-sized flapper, but that’s not the case anymore.

The latest toilet flappers range between 2″ to 4″ in size. There are a couple of factors that will determine the size of the flapper that your toilet currently utilizes.

Manufacture date

Flappers in old toilets are 2 inches across, while flappers in more recent toilet models manufactured after 2005 range from 3 to 4 inches.

Gallon Per Flush (GPF) Amount

The gallon per flush is the quantity of water that fills the tank and is then eventually flushed. There are 2 types: full flow and low flow toilets, with the latter having less water than the former.

Typically, lower-flow toilets require smaller flappers. 3″ toilet flapper valves are used on toilets with 1.6 and 1.28 GPF.

How To Determine The Correct Size Of A Toilet Flapper

Fluidmaster 502P21 PerforMAX Universal Water-Saving Long Life Toilet Flapper for 2-Inch Flush Valves, Adjustable Solid Frame Design, Easy Install, Red, 1 pack

If you’re not sure what size your toilet flapper is, there are a couple of easy methods to figure it out.

Ask In Store

The easiest way is to remove the toilet flapper and take it to your local plumbing warehouse or store and simply ask them. They have the know-how and expertise to help.


You will need to take measurements of the drain diameter where the toilet flapper sits. Generally, a 2″ toilet flapper will be the size of an orange or a baseball and measure at 1 7/8″ or 2 3/8″. A 3″ toilet flapper will be the size of a grapefruit or softball and measure close to 3″.

Make & Model Number

You will need to contact your manufacturer if the drain opening is not a standard 2″ or 3″. Look for the model number inside your toilet’s tank. The number may be inscribed on the inner walls of the tank or the cover.

Find out what size flapper is required by researching the company that manufactured your toilet and looking up their specifications.

Types of Toilet Flapper Frames

There are two types of materials used to make flapper frames, and they are as follows:

Flexible Frame Flappers

Fluidmaster 504 2-Inch Universal Chlorine Resistant, Long Lasting Flexible Frame Toilet Flapper , Red

The All Rubber Frame or flexible frame flappers are transferable with most flush valve drains because of the rubber they’re composed of. These flappers are especially compatible with angled seated valves and flush valves without any mounting posts to give a perfect seal. 

Solid Frame Flapper

A solid frame flapper is made of hard plastic and, unlike its counterpart, is only compatible with the same type as the one being replaced. It’s essentially designed for longevity. The hard plastic frame tends to be of the tank ball type and is typically more dependable.

Also Read: Types of Toilet Flappers

What Is The Flapper’s Closing Time?

The flapper closing time is important in that it can help significantly reduce your water bill. You can apply any one or all of these methods to help save water, and the following are the most effective toilet flapper features for this purpose.


Some toilets come with a variety of plastic grommets that are designed to fit at the bottom of the hole, each with a different-sized diameter opening. The tank is filled and sealed taking longer due to the smaller holes resulting in a longer flush.


This is an adjustable float that swings around the chain, impacting how fast the flapper will close. It will thus influence how long the flapper stays open. In essence, the longer the flapper stays open, the more water is flushed into the toilet bowl.


A ruler is something that can be added to reduce the gap size. In essence, with less space for the water to flow, it will take longer for the tank to fill up as well as flushing it.

In Conclusion

The toilet flapper is an important component of your toilet and one that you should be aware of in order to keep your toilet running smoothly. Be sure to know the different types and sizes as well as how to determine the correct size for your toilet.

Also, be familiar with the different types of frames and what closing time is best for saving water. By following these tips, you can be sure that your toilet will provide optimal performance. Thanks for reading!

If you liked this article about toilet flapper sizes, consider checking out these other articles below —