How to measure a toilet seat?

Presently, companies are making standard sizes of toilets. If you would like a replacement or a new one, you should know that it is still useful to measure the seat before buying it. Many people might not know how to measure a toilet seat. They can start by measuring it from the backside to the front. If the measurement turns out around 16 inches, then you need a standard size toilet. However, if it is around 18 inches or more, then opt for the elongated one.

Keep in mind that it is not easy if the seat you already have is an old one, or if you would like to have a specialty toilet seat. In any case, the measurement method will be the same. Here we will learn about it:

Take Basic Measurement of Toilet Seat

  1. Measure Length from Bolt to Front

Start by securing the measuring tape at the back of the seat and bringing it to the front end. You can note the length on the tape. You should keep in mind that the measurement has to be taken down to the center of the bowl for accurate readings.

Moreover, the tape should be in line with the bolts. Remove the plastic cover so that you could see the bolts clearly. In the end, you must take measurements from the one center of each side to the other.

  1. Measure Distance Between Bolts and Back

By using a flat-head screwdriver, lift the flap covers from the bolts. You have to now measure the distance between the bolts. Along with this, measure the spread of each bolt as well. The standards are usually 14 cm and 25 cm when it comes to the spread of bolts.

Try to order the customized one from the company if there is variation in bolt spread measurements from the standard ones. In the USA this is how to measure a toilet seat bolt, but in Europe, the standards are different so look for relevant ones.

  1. Measure Seat Width

The width measurement is crucial if you want to get the best-fitting replacement. Measure the length of outer edges by placing measuring tape from the right-center towards the left-center of the toilet seat bowl. Different brands make different sizes. Measuring the width on your own before buying would help you find the closest match very easily.

Take Measures for Specialty Seat

  1. Calculate Distance Between Bolt Holes

Place the measuring tape between the center of both bolts, and accurately note down the distance between them. This measurement is very crucial for those who are thinking about buying a specialty seat. If your seat is of not standard measurements, 15 cm for the USA and 17 cm for Europe, then you should ask the manufacturer to provide you the specialty seat.

  1. Measure Length and Width of Bowl

The next step to learn about how to measure a toilet seat is to measure the length and width of the bowl. Start by measuring the distance between the bowl front head and the center of the bolt heads. You can do the same to measure the width by using the center of the outer edge of the seat towards the center of bolt heads. The standard seats do not bother about the width of the bowl, so you can work without doing this step.

  1. Calculate Bolts and Tank Distance

If you want to buy a specialty seat, then you should try to measure the distance between the bolt centers and the tank. Other options least require this measurement, so you can skip this for seat warmers, raised seats, etc.

You should learn about the various other things before getting the specialty seat like minimum clearance of product, specifications, etc. This is to make sure that you do not spend too much money. Also, you can save it from wastage if it does not fit into your toilet after your purchase it.

  1. Measure Seat for Snap-on Attachment

For those who need new seats for potty training or raised ones for disabled family members, then this step is important. The attachments vary from the type of requirement. First, measure the length and width, and then choose an attachment that is suitable for those dimensions.

Even if you can look and just tell, you should measure it anyway so that the attachments fit perfectly into the seat. Some attachments need hinge attachment, some need clamps, etc. You should measure bolts if such is the case and requirement in your type of attachment.

Choose a Replacement Seat

  1. Buy Round Seat 16 Inches Bowl

If you are in the USA, mostly the seats are round and they come in standard size. You can choose anyone from the hardware store or home improvement outlet. This will definitely fit in your toilet. However, if you are in Europe, there are other sizes than the standard ones. So, you should ask the manufacturer about it.

Generally, it can be seen through the naked eye that the seat is round or elongated, but it is always better to double-check it. By taking measurements of length and width, you will be on the safe side.

  1. Buy Elongated Seat for 18 Inches Bowl

Another thing to keep in mind while you are learning how to measure a toilet seat is to buy the elongated seat for 18 inches bowl. In the case of an elongated seat, it is not crucial. However, in the case of the round seats, the measurement of the bolt spread the length and the width of the bowl. It will keep you on the safe side, so do not miss out on this step for the round seat.

  1. Buy Matching Seat and Bowl Shape

In Europe, you will find all types of toilet bowl shapes, like round, elongated and pointed. Everyone can identify the different shapes with the naked eye. However, for every type of these seats, the standard length is 17 inches or 43 cm. This means that if you find the right shape, it would be very easy to find the right seat for your toilet.

  1. Get Make and Model for Non-Standard Toilets

The modern seats for all types of toilets are easily available. However, it become difficult to find a good one for the older type of toilet seats. In such a case, you should contact the specialty plumbing service providers. You can also go online and search with specifications of length and width. It will help you reach out to the options that can bring a productive solution for your toilet seat.

In modern or contemporary types of toilets, there are options available other than the standard ones. So, you can just contact the manufacturing company to provide you with it. You can also maybe just search at the online websites that make them.


We are sure that the above explanation of every step about how to measure a toilet seat would be of great use for you. If you are struggling to understand where to start, you have now a complete step-by-step guideline to do this task. We wish you the best of luck!

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