How to Measure Your Toilet Rough In

When choosing a new toilet, one major measurement you need to consider is size of your toilet “rough in.” The rough in is the distance between the outlet pipe and the wall behind the toilet. Knowing your rough in size ensures your toilet will fit correctly and work properly. Toilets are available in various sizes to fit different rough ins, so having a toilet that fits your rough in is certainly possible and definitely imperative.

To find out the size of your toilet rough in, simply measure from the wall behind the toilet to the bolt caps of your current toilet, as demonstrated in the video above. Do not include baseboards in your measurements (as shown by the photo below)!


12 inches is the standard toilet rough in size, and most toilets sold in the US fit that measurement. Some homes, especially older ones, may have 10 or 14 inch rough ins. If your rough in is 10 or 14 inches, you might be limited in your selection; we recommend the TOTO Carolina 1 Piece Toilet, which is available in both rough in sizes.

Now that you know how to find your rough in size, continue your search with SUPPLY.com’s collection of toilets here