Well Water Test Results Interpreter

Type in the numbers from your lab report. You'll see what passes, what fails, what's urgent, and the usual order of treatment, all in your browser.

By Haroon Updated October 24, 2026 How we research

Independent tool, not affiliated with the EPA. It compares results to EPA public-water standards, which are the usual yardstick for private wells. Leave anything you didn't test blank.

Safety Total coliform bacteria E. coli Nitrate (as N) (NO3-N)Limit: 10 mg/L Nitrite (as N)Limit: 1 mg/L

Health metals ArsenicLimit: 0.010 mg/L (10 µg/L) LeadLimit: 0.015 mg/L (15 µg/L) action level CopperLimit: 1.3 mg/L action level UraniumLimit: 0.030 mg/L (30 µg/L) FluorideLimit: 4.0 mg/L (secondary 2.0)

Everyday water quality IronLimit: 0.3 mg/L ManganeseLimit: 0.05 mg/L (health advisory 0.3) Hardness (as CaCO₃)Limit: Treatment usually optional below 120 mg/L (7 gpg) pHLimit: 6.5 – 8.5 pH Total dissolved solids (TDS)Limit: 500 mg/L SulfateLimit: 250 mg/L ChlorideLimit: 250 mg/L ZincLimit: 5 mg/L SodiumLimit: 20 mg/L (low-sodium diets only)

What you notice (optional) Rotten egg / sulfur smell Tea-colored water that doesn't settle Sand or grit

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Frequently asked questions

Is my data sent anywhere?

No. The interpreter runs entirely in your browser. Your numbers are stored only in the page address (so you can bookmark or share it), never sent to us.

Can this replace a water treatment professional?

No. It compares your numbers to EPA limits and suggests the usual treatment types and order. Equipment must be chosen against each product’s rated limits, and health results should be discussed with your health department.

My lab used different units. What do I do?

Pick the unit next to each box. mg/L is the same as ppm; µg/L is the same as ppb. Hardness can be entered in mg/L or grains per gallon.

Sources

National Primary Drinking Water Regulations, U.S. EPA
Secondary Drinking Water Standards: Guidance for Nuisance Chemicals, U.S. EPA
Basic Information about Lead in Drinking Water, U.S. EPA
Drinking Water Advisory: Sodium, U.S. EPA
Guidelines for Testing Well Water, U.S. Centers for Disease Control and Prevention
Iron and Manganese in Private Water Systems, Penn State Extension
Water Softening (NebGuide G1274), University of Nebraska–Lincoln Extension

Sources checked October 24, 2026. Found an error? Tell us and we will fix it.

Haroon, Founder and editor
Writes The Well Owner from public-health and university extension sources. Every number on this page links to where it came from. More about us.