Contra Costa, CA Internet Speeds — Measured 2024
Real speed tests run in Contra Costa County, California during 2024 recorded a median download of 88.5 Mbps, upload of 17.4 Mbps and latency of 10.7 ms, across 145,700 measurements. That is 1.0× the US median and places it #1,063 of 2,425 US counties.
What these numbers mean here
The median is the typical connection, not the best one available. Half the tests in Contra Costa came in below 88.5 Mbps and half above. The slower quarter of connections measured under 26.6 Mbps, while the faster quarter exceeded 215.6 Mbps — a spread that usually reflects a mix of fibre, cable and older DSL lines in the same area rather than one uniform service level.
At 88.5 Mbps down and 17.4 Mbps up, a typical household here can handle HD streaming and video calls, though simultaneous heavy use may compete for bandwidth. Latency of 10.7 ms is excellent for gaming and real-time calls.
The spread of connections in Contra Costa
Measured download speed, 2024
How California has changed since 2020
Median download by year, California
State-wide measured median, Mbps
How the big providers actually perform
Median measured download speed by provider across the United States. SignalScout does not yet map which of these serve Contra Costa specifically — see how to check availability — but the ranking shows what customers of each really get.
California counties ranked
| # | County | Down | Up | Latency |
|---|---|---|---|---|
| 1 | Marin | 116.6 | 18.2 | 10.2 |
| 2 | Ventura | 115.5 | 19.7 | 9.6 |
| 3 | San Mateo | 106.9 | 23.0 | 8.0 |
| 4 | Sonoma | 104.9 | 20.6 | 10.5 |
| 5 | Orange | 99.5 | 17.6 | 8.6 |
| 6 | San Diego | 98.7 | 19.0 | 11.4 |
| 7 | Kern | 98.6 | 11.7 | 12.4 |
| 8 | Solano | 96.1 | 19.4 | 11.5 |
| 9 | Santa Cruz | 94.2 | 16.3 | 11.6 |
| 10 | Imperial | 93.8 | 11.1 | 13.6 |
| 11 | Santa Barbara | 93.1 | 21.6 | 11.5 |
| 12 | Monterey | 91.6 | 17.1 | 10.9 |
See all 55 counties in California →
Check a specific address in Contra Costa
County figures describe the area. To look up a specific street address and compare it with somewhere else you are considering, use SignalScout directly.
Common questions
What is the average internet speed in Contra Costa, CA?
Speed tests run in Contra Costa during 2024 recorded a median download of 88.5 Mbps, a median upload of 17.4 Mbps and median latency of 10.7 ms, across 145,700 measurements collected by Measurement Lab.
Is internet in Contra Costa faster or slower than the US average?
Faster. The median measured download here is 88.5 Mbps against a US median of 85.2 Mbps, which ranks Contra Costa #1,063 out of 2,425 counties nationally.
Are these advertised speeds or real ones?
Real ones. These are aggregated results of speed tests run by actual people on their own connections, published in the public domain by Measurement Lab. They reflect the plans residents actually buy, which is typically well below the fastest plan a provider sells.
Which internet providers serve Contra Costa?
SignalScout does not yet map provider availability by address — that data comes from FCC filings that require a registered account for bulk access. The page shows how major national providers perform, and the FCC National Broadband Map lists filed availability by address.
Check a real address
See the measured download, upload and latency for any US address, plus a Connectivity Score ranked against every county in the country.