2025 Compare Cities People:
Boulder, CO vs Foster City, CA

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Highlights
- Foster City is 0% more densely populated than Boulder.
- People are 95.2% more likely to be married in Foster City.
- The Median Age is 10.7 years older in Foster City.
 Boulder, COFoster City, CAUnited States
 Population  Unlock33,511329,725,481
 Female Population48.5%  Unlock50.5%
 Male Population51.5%  Unlock49.5%
 Median Age  Unlock39.638.4
 space3
 Population - 201097,724  Unlock309,327,143
 Population - 2000  Unlock28,803285,036,114
 Population - 199083,312  Unlock251,960,433
 Pop. 2000 to Now  Unlock14.2%15.6%
 Pop. 1990 to Now29.2%  Unlock30.8%
 space4
 Population Density  Unlock8,828.093.4
 Land Area26.3  Unlock3,531,905.4
 Water Area  Unlock16.0264,836.8
 space
 Est. Total Population By Age
 Boulder, COFoster City, CAUnited States
 Age 0 to 42.7%  Unlock5.9%
 Age 5 to 9  Unlock7.2%6.1%
 Age 10 to 143.6%  Unlock6.6%
 Age 15 to 17  Unlock3.9%3.9%
 Age 18 to 2016.2%  Unlock4.0%
 Age 21 to 24  Unlock2.7%5.2%
 Age 25 to 3416.3%  Unlock13.8%
 Age 35 to 44  Unlock16.9%12.9%
 Age 45 to 5410.3%  Unlock12.6%
 Age 55 to 59  Unlock5.8%6.7%
 Age 60 to 644.2%  Unlock6.3%
 Age 65 to 74  Unlock8.5%9.6%
 Age 75 to 843.1%  Unlock4.5%
 Age 85 and over  Unlock2.5%1.9%
 space1
 Race
 Boulder, COFoster City, CAUnited States
 White78.3%  Unlock59.4%
 Black  Unlock2.4%12.2%
 Asian5.9%  Unlock5.6%
 Native American  Unlock0.2%0.6%
 Hawaiian, Pacific Islander0.0%  Unlock0.2%
 Other  Unlock0.1%0.4%
 Two or More Races3.5%  Unlock3.2%
 Hispanic  Unlock8.6%18.4%
 space2
 Marriage & Family
 Boulder, COFoster City, CAUnited States
 Married Population31.9%  Unlock49.8%
     Currently Married  Unlock61.1%48.0%
 Married but Separated0.7%  Unlock1.8%
 Single Population  Unlock37.6%50.2%
 Never Married56.1%  Unlock33.8%
 Divorced  Unlock6.2%10.8%
 Widowed2.5%  Unlock5.6%
 space5
 Household Size  Unlock2.672.60
 Households42,610  Unlock124,010,992
 Family Households  Unlock8,85780,755,759
     Married couple, w/children33.3%  Unlock30.5%
     Married couple, no children  Unlock40.5%42.9%
 Non Family Households25,269  Unlock43,255,233
     Single householder, w/children  Unlock7.8%15.8%
     Single householder, no children8.5%  Unlock10.8%
Reviews for Boulder    55 Reviews

Outside of the university, Boulder had a very distinctive "wealthy hippy" feel. A lot of alternative medicine and a matching ethos. This is changing some among my  More

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We moved here from Texas about 4 years ago and love it here! The amazing sense of community and high regard for the environment are two of the main reasons we love  More

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Over 5 years ago

Most people do much worse than Boulder. I'm the most critical person I've ever met who is never happy or satisfied -- so that's a pretty huge compliment.   More

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Reviews for Foster City    4 Reviews

Over 17 years ago

Built on lagoons, great climate, good schools, lots of soccer and other sports for kids, plenty of parking and  More

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Over 18 years ago

A great city to raise a family, safe, great weather around the year, good schools and plenty of recreation. But only if you can afford the hight cost of  More

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Landlords are able to command and receive high rent due to the following attributes: safety, weather and cleanliness of Foster City. The lagoon, waterways and gardens  More

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