Measuring for a New Toilet
Updated February 20, 2026
Key Takeaway
Three measurements determine compatibility: rough-in distance, bowl shape, and clearances. Five minutes of measuring prevents an expensive mistake.
Overview
Three measurements determine compatibility: rough-in distance, bowl shape, and clearances. Five minutes of measuring prevents an expensive mistake.
What to Know
Buying Tips
- Measure from WALL, not baseboard.
- 12-inch rough-in is standard and nearly universal.
- Elongated is more comfortable but verify front clearance.
- Take a photo of measurements for shopping.
Common Mistakes
- Measuring from baseboard (adds 1/2-3/4 inch error).
- Buying 12-inch for a 10-inch rough-in.
- Elongated bowl that blocks the door.
- Forgetting side clearances.
Bottom Line
Measure rough-in from wall to bolt center. Verify bowl shape fits. Check clearances. 12-inch rough-in with elongated fits 95% of bathrooms.