How to Measure For a New Toilet Seat

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It’s important to know how to measure for a new toilet seat before you change the one that you have. You want one that is going to fit properly. Individuals in your home may have different needs, and you want a seat that will accommodate them. This guide will show you how to measure and pick the best seat for your toilet.

Buying a toilet seat

You’ll have several choices when it comes to your toilet seat. Plastic ones are ideal as they have parts that don’t rust. However, they aren’t as visually appealing as wooden seats which tend to be fancier.  A wooden seat will have metal parts, and these can rust and corrode over time. You will have to decide what type you want to buy. The installation of the seat is a simple process, but you first have to measure things. Here is how you go about that.

Why you need to measure

While toilet seats tend to come in a standard size, not all toilets have a standard seat. If you don’t measure, you may buy a seat that is too small or large for the bowl and have to take it back. If you open the package, the store will usually not refund your money as the product is considered used.

Measuring your seat

  • You want to measure from the post hole to the post hole. This is at the back of the seat.
  • Standard seats are around 155mm or 5 and ½ inches between the two holes.
  • You want to measure the toilet bowl width at the broadest area.
  • Take a standard measuring tape and place this at the center front of the bowl. Stretch your tape to the center of the hinges between the seat post holes.
  • Record the measurements and take them with you to the store.
  • If you don’t know what to buy, ask a clerk for assistance.


Now you know how to measure for a new toilet seat, so it’s time to install. Putting a seat together is quite easy. Just follow the instructions provided. You can often do it with a simple wrench and it should take you around five minutes to complete. Put the bolts through the holes and then secure them with the nuts provided in the package that came with the seat.

Seat shapes

In the USA there are standard seat sizes.

  • The round size is around 16.5 inches
  • The elongated seat is around 18 inches. This type of seat is used in commercial areas


Once you know how to measure for a new toilet seat, you must pick one out. Here are the common materials you must work with.

High-impact plastic

This is usually all plastic or a plastic coating over a wood seat. There are various styles to choose from. You can get them in different colors, and some have fancy designs and prints on them.


There are seats available in different woods. This can include bamboo, natural wood, and fiberboard. Wood is hygienic, and the surface stays quite clean when compared to plastic. The downside is it needs to stay dry, or the wood could stain and become damaged over time when exposed to the water.

Special seats

There are special seats available that have more cushioning for people with medical problems. There are also seats you can buy which are elevated or come with handlebars for the elderly. If you have medical issues, your health practitioner can help you pick out the right seat for your issue.

Open front seat

This seat has a piece missing in the front of the seat. They are a U shape. These are common in hospitals and airport restrooms. They protect the toilet from urination drips. These seats also reduce the spread of diseases as the genital area doesn’t touch the seating area. The seat is more sanitary as there isn’t as much reaching and moving around like you need to do on a regular seat.

Elevated and raised seats

These seats are larger than normal and higher too. They are mainly used to help people recover from surgery when they have less mobility. There are many different types. Your doctor can help you find one that meets your medical needs. You can often find them with more padding if you require that.

Child seat

The child seat has an extra part to it. It’s designed to help toddlers learn how to potty train. They are smaller to accommodate smaller children so they don’t fall in the toilet. There are numerous styles, so you’ll need to find one for your needs.

OEM seat

This is a seat that comes from the manufacturer. OEM means original equipment manufacturer. When companies release new toilets, they ask seat manufacturers to produce seats specifically designed for their new toilet models. They want seats that fit perfectly with the new bowl in case the original seat must be replaced.

These seats are not often found at your local retailer. Instead, you will often need to go to a plumbing shop to obtain one.  The ones in the store are universal in size, but your specific toilet may have a unique seat. If it needs replacing you can find a manufacturer’s seat in plumbing shops. They may also be able to order a seat for you. Make sure you know the toilet bowl model and manufacturer name, so you get the right seat.


  • Clean the entire toilet before you install the seat for sanitary purposes.
  • Read all the instructions for the seat and make sure you have all the parts and tools required before you begin.
  • Don’t overtighten the bolts on the seat. Many of them are made of plastic, and they may break if you over tighten. They should be snug, so the seat doesn’t move but is also not too tight.
  • If the seat has screws check these to ensure they are tight. Like the bolts, you don’t want to over-tighten them.
  • Don’t force parts together; everything should go together smoothly. You can break parts if you force them together.
  • Some movement in a toilet seat is normal. If it moves too much, check to see that the bolts are snug.

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