Bidet Seat Fitment

If you are contemplating purchasing a bidet seat or bidet attachment, but not sure if it’s compatible with your toilet, this guide may help you. If you still have questions after reading, please contact us!

Our bidet seats and attachments fit on most modern toilets; however, they may not be compatible with some older or specialty models. French curve toilets are notoriously difficult when it comes to bidet seats. If your toilet looks like the one below, check out our blog post on French curve toilets.


Kohler San Raphael

Most of our bidet seats come in either elongated or rounded models to fit almost any toilet. Our bidet attachments fit under both elongated and rounded toilet seats. Some models are only elongated, so make sure you know what you are buying!

There are two main types of toilet bowls: elongated and round. Older and more basic toilets are round, while more modern, toilets have an elongated bowl.

Elongated toilets are more oval-shaped than round, as shown in the diagram below. If you're uncertain about which type you have – here’s how to measure your toilet for a bidet seat or attachment:

  • To measure the length of the bowl, locate the two mounting bolts at the seat hinge. From there, measure to the very front of the toilet bowl in a straight line. That straight line measurement will be about 16-1/2 inches if the bowl is round, and 18-1/2 inches if your bowl is elongated. Mounting brackets for bidet seats allow for some adjustment in case your bowl is not exactly either of the two values. 

Check for round or elongated bowls
  • You'll also need to measure the distance between the toilet bolt holes.  Any distance shorter than 5.5 inches or greater than 7.5 inches will likely be incompatible.
  • The last measurement you’ll need to confirm is the distance between the bolt holes and the toilet tank, which should be no less than 1.5 inches.

Check for clearance behind and between bolts