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Contra Costa County, CA Demographics

Contra Costa County, CA is the 9th most populous of 58 counties in California, with 1,165,940 residents across 717 square miles. That is about 1,626 people per square mile.

At the 2020 census

Population 1,165,940
Land area 717 sq mi
Density 1,626 / sq mi

Data: 2020 Census · American Community Survey 2024

How Contra Costa County compares to the US

We're computing this county's comparison table — check back shortly. Population, land area, and density above are already exact.

Central Location: Contra Costa County, CA

Measured from the county's main population center using 2020 census blocks.

We're computing the drive-time and radius areas around Contra Costa County, CA — check back shortly. Meanwhile you can drop a pin anywhere in the radius tool.

Census tracts in Contra Costa County, CA

Name Population Sq mi Per sq mi
Census Tract 3551.15 10,242 0.9 12,026
Census Tract 3552.01 9,199 1.8 5,118
Census Tract 3032.02 9,125 1.4 6,344
Census Tract 3451.12 8,830 3.3 2,692
Census Tract 3820 8,334 0.8 10,911
Census Tract 3720 8,009 0.6 13,307
Census Tract 3020.14 7,906 1.5 5,331
Census Tract 3020.09 7,817 2.0 3,837
Census Tract 3080.01 7,770 1.4 5,397
Census Tract 3770 7,725 0.5 16,069
Census Tract 3320 7,719 1.2 6,661
Census Tract 3630 7,612 1.7 4,480
Census Tract 3072.05 7,484 1.2 6,331
Census Tract 3020.07 7,412 1.7 4,429
Census Tract 3310 7,337 1.1 6,746
Census Tract 3462.04 7,334 5.0 1,458
Census Tract 3810 7,261 0.8 9,580
Census Tract 3790 7,255 0.7 11,154
Census Tract 3031.04 7,206 1.7 4,303
Census Tract 3540.02 7,200 5.6 1,281
Census Tract 3342 7,194 2.6 2,745
Census Tract 3142 7,168 1.9 3,800
Census Tract 3551.09 7,167 1.2 6,225
Census Tract 3020.05 7,134 1.4 5,166
Census Tract 3050 7,064 3.1 2,257
Census Tract 3551.21 7,053 1.9 3,760
Census Tract 3200.04 7,038 2.3 3,083
Census Tract 3031.06 7,021 11.6 603
Census Tract 3592.03 7,013 1.4 4,900
Census Tract 3452.03 6,966 10.4 670
Census Tract 3031.07 6,966 1.3 5,197
Census Tract 3760 6,941 0.5 14,979
Census Tract 3211.02 6,826 2.1 3,319
Census Tract 3141.02 6,812 1.8 3,764
Census Tract 3690.01 6,771 0.6 10,844
Census Tract 3551.11 6,685 0.9 7,120
Census Tract 3032.07 6,600 2.2 3,067
Census Tract 3451.14 6,591 2.2 3,005
Census Tract 3290 6,579 1.1 6,206
Census Tract 3131.05 6,559 0.8 7,797
Census Tract 3220 6,528 1.7 3,863
Census Tract 3660.02 6,525 0.4 16,305
Census Tract 3211.01 6,498 1.7 3,896
Census Tract 3451.05 6,484 1.4 4,571
Census Tract 3400.01 6,419 1.0 6,128
Census Tract 3132.06 6,342 0.7 9,493
Census Tract 3451.15 6,309 6.1 1,041
Census Tract 3522.01 6,266 2.7 2,343
Census Tract 3451.01 6,264 0.8 7,509
Census Tract 3580 6,237 2.6 2,357
Census Tract 3382.04 6,234 1.0 6,095
Census Tract 3470 6,230 9.8 636
Census Tract 3500 6,224 3.3 1,879
Census Tract 3373 6,147 1.7 3,640
Census Tract 3592.02 6,130 3.7 1,638
Census Tract 3100 6,106 0.8 7,989
Census Tract 3650.02 6,085 2.2 2,711
Census Tract 3710 5,995 0.5 11,792
Census Tract 3451.11 5,990 0.9 6,705
Census Tract 3383.02 5,981 2.7 2,241
Census Tract 3332 5,961 0.9 6,494
Census Tract 3512 5,953 3.5 1,703
Census Tract 3922.01 5,945 3.7 1,589
Census Tract 3671 5,941 0.7 8,839
Census Tract 3131.06 5,879 5.0 1,180
Census Tract 3640.02 5,868 0.8 7,191
Census Tract 3071.02 5,824 0.6 9,409
Census Tract 3551.07 5,793 31.7 183
Census Tract 3452.05 5,775 1.6 3,682
Census Tract 3672 5,754 0.5 11,271
Census Tract 3461.02 5,748 7.8 735
Census Tract 3040.01 5,748 11.2 515
Census Tract 3250 5,733 1.1 5,055
Census Tract 3521.02 5,724 8.7 656
Census Tract 3362.02 5,720 0.3 21,545
Census Tract 3132.04 5,704 6.6 869
Census Tract 3110 5,668 0.6 9,044
Census Tract 3551.12 5,636 98.1 57
Census Tract 3060.03 5,615 0.7 8,113
Census Tract 3212 5,589 0.9 6,306
Census Tract 3300 5,587 0.8 6,696
Census Tract 3240.02 5,519 0.8 7,052
Census Tract 3010 5,514 35.2 157
Census Tract 3141.03 5,513 2.2 2,512
Census Tract 3591.02 5,496 0.8 6,911
Census Tract 3551.26 5,496 5.3 1,037
Census Tract 3560.02 5,481 40.9 134
Census Tract 3680.01 5,467 0.3 18,423
Census Tract 3032.09 5,403 1.5 3,534
Census Tract 3020.11 5,401 6.1 883
Census Tract 3382.03 5,379 0.6 8,834
Census Tract 3410 5,374 1.6 3,448
Census Tract 3020.12 5,348 1.1 4,671
Census Tract 3080.02 5,289 1.5 3,479
Census Tract 3591.05 5,276 0.7 7,641
Census Tract 3451.03 5,270 1.3 4,200
Census Tract 3591.03 5,269 1.0 5,383
Census Tract 3650.03 5,215 1.0 5,333
Census Tract 3381.01 5,161 0.4 11,847
Census Tract 3490 5,151 1.4 3,776

Showing the 100 most populous of 241 — the rest are shown on the map.

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About this page

This page shows demographics for a US county from the 2020 census and the American Community Survey: population, land area, density, urban share, and how the county compares to national averages for income, housing, age, and more.

Counties subdivide into census tracts, listed below with their populations. The drive-time and radius tables measure the population around the county's main population center.

Read how BlockAtlas computes population within an area →