Check the air and drinking water in any US ZIP code.
Type a ZIP code and get two scores back in a second: one for the air, one for the drinking water. Both come from the EPA's own records for that county. Where the EPA has no monitor, we say so instead of guessing.
Showing Los Angeles County, CA
ExampleZIP 90210Los Angeles County, CA
Air
27 / 100
On 90% of measured days the air stayed at or below AQI 147, which EPA calls “unhealthy for sensitive groups”.
Drinking water
99 / 100
199 utilities serving 10,058,958 people. 21 unresolved health-based violations on record.
Combined 63 / 100 · Mixed
In plain terms: on most days the air here rates unhealthy for sensitive groups, and the 199 utilities serving it have 21 unresolved health-based violations, though the systems involved serve under 1% of the people here.
The two halves disagree sharply here, so the combined number hides more than it shows — read the air and water scores separately.
Scored for Los Angeles County, CA, the county holding most of ZIP 90210. Sources: EPA AirData annual AQI by county, 2025 · EPA SDWIS/ECHO drinking-water violations, 2026Q2.
See the full breakdown for 90210 →Every number is an EPA record, never an estimate.
48% of US ZIP codes have no EPA air monitor in their county. We say so instead of guessing.
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Which states have the cleanest air and water?
- Cleanest airHawaii80 / 100
- Worst airCalifornia45 / 100
- Cleanest drinking waterNorth Dakota100 / 100
- Worst drinking-water recordPuerto Rico53 / 100
Scores are out of 100. Air is the EPA's 2025 monitoring year, the latest complete one; water is EPA violation records through 2026Q2. Each row opens the full state ranking.
Everything you can look up here
Look up a place
- Air & Water Score by ZIP CodeEnter a ZIP code and get one score for the air and one for the drinking water, each traced to an EPA record.
- Compare Two ZIP CodesPut two ZIP codes side by side and see which has the better air, the better water, and by how much.
- Drinking Water by UtilityLook up your water utility by name and see every violation on its EPA record for the last five years.
- Air Quality Trend by CountyTen years of EPA air readings for any county, and a plain call on whether it has gotten better, worse, or stayed the same.
Compare across the country
- Cleanest Air by StateEvery state ranked by how clean its measured air is, with the monitored counties behind each rank.
- Worst Water Violations by StateEvery state ranked by the drinking-water violations on its utilities' EPA records, worst first, down to the county.
- Best & Worst Counties for Air and Water QualityThe 100 best and 100 worst US counties for air and water together, with a ZIP code to try for each.
- Cleanest Drinking Water by StateEvery state ranked by the drinking-water violations on its utilities' EPA records, cleanest first.
How the score is made
- Your ZIP is matched to its county. The EPA keeps its records by county, not ZIP code, so we use the county that holds most of your ZIP's land and name it on the result.
- Two records become two scores. The air score comes from a year of readings at the EPA monitors in that county. The water score comes from the violations on record for the utilities serving it, over the last five years, weighted by how many people each one serves.
- A missing record stays missing. No monitor means no air score, not a borrowed one from the next county. When the two halves disagree sharply, we say so rather than averaging them into a number that hides the problem.
The full method, formulas and sources are on the About page and under every tool.
Worth reading before you decide
- What Your Air & Water Score Actually MeansThe score is two EPA records folded into one number. What the air half and the water half each measure, why a single number can hide more than it shows, and how to read the breakdown underneath it.
- How to Compare Air and Water Quality Between Two ZIP Codes Before You MoveA side-by-side score is easy to misread as a verdict. What actually drives a gap between two ZIP codes, when the composite number is the wrong thing to compare, and a short checklist for using the comparison tool well.
- Why One Big Water Utility Can Move a Whole State's RankingA state's drinking-water rank weights each utility by the people it serves. See the arithmetic with a worked example, and how to read a low rank.