August 07, 2025

Round vs. Elongated: Will a Bidet Attachment Fit Your Toilet?

Choosing the right bidet attachment isn’t just about features or price — it's about fit. One of the most common concerns among new customers is whether a bidet attachment will properly fit their toilet. In this guide, we'll dive into every detail you need to confidently assess your toilet's compatibility, with a focus on round vs. elongated toilets, and other installation factors you shouldn't overlook.

1. The Two Most Common Toilet Shapes: Round vs. Elongated

Most toilets fall into one of two shape categories:

🚽 Round Toilets

Shape: Shorter and more circular.
Length: Approximately 16.5 inches (42 cm) from the mounting holes to the front edge.
Common In: Older homes, smaller bathrooms, or space-constrained environments.
Compatibility Notes: Most bidet attachments will fit, but may appear slightly oversized on the bowl.

🚽 Elongated Toilets

Shape: Oval and more elongated.
Length: Approximately 18.5 inches (47 cm) from mounting holes to front edge.
Common In: Modern homes, offices, luxury bathrooms.
Compatibility Notes: Elongated seats tend to provide better support for bidet attachments, allowing them to sit more naturally and securely.

2. How to Measure Your Toilet for a Bidet Attachment

Before purchasing, grab a measuring tape and follow these steps:

Bolt Hole Spacing: Measure the distance between the two bolt holes at the back of the seat.
- Standard U.S. spacing is 5.5 inches (14 cm).
Toilet Bowl Length: From the center of the bolt holes to the front edge of the bowl:
- ~16.5" = Round
- ~18.5" = Elongated
Clearance Around the Seat Bolts: You should have at least 1.5 inches (4 cm) of flat space around the bolt area to securely install the bidet attachment.
Water Supply Location: Make sure the cold water supply valve is accessible — usually located on the wall behind or beside the toilet.

3. Less Common Toilet Types (And What to Watch Out For)

🌊 One-Piece Toilets

Integrated tank and bowl structure.
Limited flat installation area near bolts, making it difficult to securely install the bidet attachment.

⛩ Wall-Hung Toilets

Typically have concealed mounting systems and reduced space behind the seat.
Insufficient clearance to install standard bidet attachments securely.

🏠 Skirted Toilets

Feature a skirt around the base for aesthetic purposes.
May hide the supply valve or limit access for T-valve installation.
A flexible hose extension is often needed.

Compact Toilets

Found in RVs, small apartments, or mobile homes.
Smaller bolt spacing or shallow bowls can affect fit.

4. Common Installation Questions

❓ Will my toilet seat still close properly?

Yes, if installed correctly. The nozzle structure is designed to be thin enough not to interfere with the seat.

❓ Will the seat be lifted?

Bidet attachments can slightly raise the back of your toilet seat by a few millimeters. Most users find this negligible.

❓ Can I install a bidet if I rent?

Yes! Bidet attachments are non-electric, non-permanent, and easily removable — ideal for rental apartments.

5. Important Compatibility Notice for Your Bidet Attachment

While Samodra bidet attachments are designed to fit most standard two-piece toilets (approximately 99% compatibility), please be aware that certain toilet types may present compatibility challenges:

✅ Compatible:

Standard Two-Piece Toilets:
- Clear separation between toilet tank and bowl.
- Standard bolt spacing and flat installation area for easy attachment.

❌ Usually Not Compatible:

One-Piece Toilets: Limited flat installation area near bolts.
Wall-Hung Toilets: Typically have insufficient clearance behind the seat.

📐 Check Before You Buy (for Samodra Bidet Attachments):

Center of Toilet to Wall (Minimum): 11.5 inches
Center to Edge of Toilet (Maximum): 7.18 inches
Distance Between Seat Bolts: 3.5 to 8.25 inches
Bolt to Toilet Tank (Minimum): 1 inch
Bolt to Front Edge of Bowl: 1.25 to 3.5 inches

Please measure your toilet carefully and confirm compatibility before purchasing. If you have questions or uncertainties, contact Samodra's support team with your toilet's dimensions or photos—we're here to help ensure the perfect fit for your bathroom upgrade!

6. Summary: Quick Compatibility Checklist

🔢 Standard Bolt Distance: 5.5 inches (14 cm)?
🔢 Flat space around bolts: 1.5" (4 cm) or more?
🔢 Toilet bowl shape measured? Round (~16.5") or Elongated (~18.5")?
🔢 Water valve accessible?
🔢 Any skirted or curved tank design?

If all these boxes are checked, you’re ready to upgrade your toilet with confidence.