Terms of use

The data here is for general information. It is not a water test and not advice about your health.

Hardness numbers come from the TapWaterData US Water Hardness dataset under CC BY 4.0, and violation records from EPA. Both can be out of date or wrong for your address. Check your utility's annual water quality report, or test your own water, before you buy equipment.

The softener calculator gives an estimate from the numbers you enter. Follow the manufacturer's sizing guidance and local plumbing code when you install anything.

You may quote and reuse our figures with a link back to this site and credit to TapWaterData and EPA. We provide the site as is, without warranties, and we are not liable for decisions made from it.

Contact: [email protected].