Diablo is a community in Contra Costa County, California, home to about 1,232 people across 1.4 square miles. Its ZIP code is 94528.
Homes sold for a median of $1,258 per square foot in the three months ending August 2026, a buyer’s market.
Each card is that ZIP code’s whole market, including any part outside Diablo. Seller’s market: under 4 months of supply; buyer’s market: over 6. Methodology
We’re writing up Diablo’s story and what everyday life there is like, for people thinking about moving in.
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| Nearest major airport | Oakland San Francisco Bay Airport (OAK)16 miles away |
|---|---|
| Nearest city of 250,000+ | Oakland, CA15 miles away |
| Nearest city of 1 million+ | Los Angeles, CA330 miles away |
Straight-line distances from the center of Diablo; driving is longer.
Source: Airports from OurAirports (scheduled passenger service); city centers and populations from the U.S. Census Bureau.
Source: Members of Congress from the congress-legislators project; districts from the Census Bureau’s relationship files; governor and mayor from Wikidata.
Diablo had 1,255 residents in the 2020 census, up 27% since 2000.
It’s the 1008th largest of 1,563 towns in California by population.
Contra Costa County grew from 18,046 residents in 1900 to 1,165,927 in 2020.
Contra Costa County, 1900–2020
Source: U.S. Census Bureau decennial censuses (counties 1900–1990 from the Bureau’s historical county file).
Average highs peak around 83°F in summer, and winter lows average 41°F. About 26.1 inches of rain and melted snow fall in a typical year, with about 1 inches of snow.
Source: NOAA 1991–2020 climate normals, Mt Diablo Junction, CA weather station (3 miles away).
343,690 jobs at 25,932 businesses in Contra Costa County. The biggest industries by employees:
Source: U.S. Census Bureau County Business Patterns 2023 (private employers; jobs counted where people work).
3 doctors and other health care providers list an office in Diablo.
Nearest hospitals
Providers with an office here
| Mental health providers | 3 |
|---|
Source: Hospitals from CMS Hospital General Information (ratings are CMS overall star ratings); straight-line distances; providers from the CMS National Plan and Provider Enumeration System (NPPES), by practice address and primary specialty.
Grocery stores
Pharmacies
Libraries
Museums
Theaters and performance venues
Counts are within about 1 mile of the center of town.
Source: Map data © OpenStreetMap contributors (openstreetmap.org/copyright), as mapped by volunteers; it can miss places or include closed ones.
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Town boundaries don’t always match ZIP codes: a ZIP code can cross into neighboring towns, and a town can share a ZIP code with its neighbors. Facts describe the town itself; market figures describe whole ZIP codes.