Across 32 directional measures we can compare, Foster City leads on 18 and Key Biscayne on 14. Counting measures is not an overall verdict: their importance depends on your priorities. Median rent is 0% higher in Foster City, and so is median household income.
The Citytistics read
- After the median rent, with other prices set to the US average, the median household has about $158,100 a year left in Foster City and $132,000 in Key Biscayne. Money goes further in Foster City, by about $26,100 a year.
- A household earning Foster City's median of $199,143 would need about $209,000 in Key Biscayne to keep the same money after rent and local prices.
- Between the 2019 and 2024 surveys, pay outran rent by 2.9 points a year in Foster City, and rent outran pay by 2.9 points a year in Key Biscayne.
Which fits you?
Both start on the Citytistics Index (CTX). Move the sliders to weigh what matters to you and the score becomes your own mix.
Your weights
Top 2 of 2 matching places. Places in the top 1% show their national rank.
| # | Place | CTX | Affordability | Economy | Education | Safety | Commute | Amenities | Growth |
|---|---|---|---|---|---|---|---|---|---|
| 01 | Key Biscayne, FLComposite 65.3 / 100Low crime coverage | 87 | 17 | 93 | 98 | 98 | 59 | 45 | 23 |
| 02 | Foster City, CAComposite 57.4 / 100 | 70 | 24 | 74 | 97 | 77 | 25 | 63 | 14 |
CTX is the Citytistics Index: better than that share of the places we rate. It tops out at 99, so the top 1% show their national rank (#1 is best). Change any weight to rank on your own mix. How the CTX is built
Every measure
The dots show where each place sits among the 6,645 places we track. The bar is the median. A small dot after a value marks the better one.
| Measure | Foster City | Key Biscayne | Among all places |
|---|---|---|---|
| Cost of living | |||
| Median gross rent1 | $3,501 | $3,501 | |
| Rent to income1 | 21.1% | 23.1% | |
| Home price to income1 | 9.2x | 8.7x | |
| Prices vs US average2 | 115.6 | 114.2 | |
| Fair market rent, 2 bedrooms3 | $3,697 | $2,564 | |
| HUD area median income4 | $200,800 | $89,800 | |
| Housing | |||
| Property tax paid (median)1 | $10,001 | $10,001 | |
| Median home value1 | $1,838,200 | $1,575,300 | |
| Home prices, 1-year change5 | -0.6% | 2.8% | |
| Home prices, 5-year change5 | 22.5% | 79.5% | |
| Homeownership1 | 50.8% | 66.5% | |
| Renters paying 30%+1 | 42.1% | 65.7% | |
| Owner costs with a mortgage1 | $4,001 | $4,001 | |
| Vacant homes1 | 4.5% | 32.4% | |
| Median year built1 | 1976 | 1977 | |
| Jobs and income | |||
| Median household income1 | $199,143 | $181,505 | |
| Income per person1 | $98,585 | $106,219 | |
| Unemployment1 | 4.8% | 2.9% | |
| Average annual pay6 | $214,295 | $81,818 | |
| Pay growth, 1 year6 | 9.1% | 5.4% | |
| Jobs6 | 411,346 | 1,276,535 | |
| Poverty rate1 | 4.1% | 5.5% | |
| Mean commute1 | 29 min | 24 min | |
| Works from home1 | 34.2% | 34.6% | |
| Commutes by transit1 | 2.9% | 3.3% | |
| People | |||
| Population1 | 32,792 | 14,791 | |
| Population change since 20207 | -4.1% | 0.1% | |
| Median age1 | 39.5 | 42.2 | |
| Bachelor's or higher1 | 73.8% | 77.2% | |
| High school or higher1 | 96.2% | 96.1% | |
| Household size1 | 2.5 | 3.0 | |
| Born abroad1 | 49.5% | 58.1% | |
| No health insurance1 | 2.2% | 1.8% | |
| Homes with broadband1 | 98.2% | 92.6% | |
| Moving | |||
| Moved here in the past year1 | 8.2% | 10.5% | |
| Moved from another state1 | 2.4% | 2.4% | |
| Net movers per 1,000 people8 | -10.7 | -18.7 | |
| Income of households moving in8 | $167,342 | $127,200 | |
| Income of households moving out8 | $186,435 | $78,108 | |
| Local life | |||
| Restaurants and bars per 10k9 | 27.2 | 22.2 | |
| Shops per 10k9 | 24.6 | 39.5 | |
| Arts, recreation and fitness per 10k9 | 4.7 | 5.9 | |
| Doctors' offices and clinics per 10k9 | 23.5 | 33.8 | |
| Child care centers per 10k9 | 4.8 | 2.8 | |
| Parks per 10k10 | 21.6 | 5.4 | |
| Playgrounds per 10k10 | 9.8 | 3.4 | |
| Grocery stores per 10k10 | 1.8 | 0.7 | |
| Restaurants, cafes and bars per 10k10 | 6.4 | 6.1 | |
| Libraries per 10k10 | 0.9 | 1.4 | |
| Named paths and bike trails10 | 9.7 | 0.1 | |
| Transit stops per sq mi10 | 39.6 | 48.1 | |
| Nearest National Park Service site11 | 19.4 | 13.1 | |
| National Park Service sites within 60 miles11 | 9 | 2 | |
| National Register listings12 | 64 | 194 | |
| Founded or incorporated13 | 1971 | 1991 | |
| Safety | |||
| Violent crime per 100k14 | 71 | 9 | |
| Property crime per 100k14 | 756 | n/a | |
| Schools | |||
| Public schools15 | 174 | 2 | |
| Public school students15 | 82,403 | 2,455 | |
| Students per teacher15 | 20.0 | 19.5 | |
| Climate | |||
| July average high16 | 74°F | 91°F | |
| January average low16 | 42°F | 58°F | |
| Average temperature16 | 57°F | 76°F | |
| Annual precipitation16 | 28.7 in | 57.5 in | |
| Hazards and air | |||
| Natural hazard risk17 | 99.2 | 99.6 | |
| Hurricane risk17 | n/a | 100.0 | |
| Tornado risk17 | 30.6 | 98.7 | |
| Wildfire risk17 | 92.0 | 96.8 | |
| Heat wave risk17 | 91.6 | 99.3 | |
| Median air quality index18 | n/a | 47 | |
| Good air days18 | n/a | 56.4% | |
Data bundle checked 2026-11-14; individual source vintages vary. Rent needed at the 30% line: Foster City $140,040, Key Biscayne $140,040 a year.
Sources and methods
The small numbers beside each measure point here. Links go to the publisher.
- American Community Survey 5-year estimates · US Census Bureau · 2020 to 2024 estimatesTables B01002, B01003, B05002, B07003, B08013, B08301, B15003, B17001, B19013, B19301, B23025, B25002, B25003, B25010, B25035, B25064, B25070, B25077, B25088, B25103, B28002, S2701
- Regional Price Parities · US Bureau of Economic Analysis · Latest release, retrieved 2026-11-14
- Fair Market Rents · US Department of Housing and Urban Development · Fiscal year 2027
- Income Limits · US Department of Housing and Urban Development · Fiscal year 2026
- House Price Index · Federal Housing Finance Agency · Latest release, retrieved 2026-11-14
- Quarterly Census of Employment and Wages · US Bureau of Labor Statistics · 2025 annual averages
- Population Estimates · US Census Bureau · Vintage 2025
- SOI Tax Stats, county-to-county migration · Internal Revenue Service · Tax years 2022 to 2023Counts tax returns and the people on them; flows under 20 returns are suppressed.
- County Business Patterns · US Census Bureau · 2023 data
- OpenStreetMap · © OpenStreetMap contributors, available under the Open Database License (ODbL) · Map data as of 2026-11
- National Park Service sites · Wikidata (CC0), units operated by the National Park Service · Retrieved 2026-11
- National Register of Historic Places · National Park Service · Listings through 2026-05-22
- Wikidata · Wikimedia Foundation (CC0) · Retrieved 2026-11
- Crime Data Explorer · Federal Bureau of Investigation · 2025 data
- Common Core of Data · National Center for Education Statistics · 2024 release
- 1991-2020 climate normals · NOAA National Centers for Environmental Information · Series updated 2026-11-05Averages for 1991 to 2020 computed from NOAA's county climate series (nClimDiv).nClimDiv county series
- National Risk Index · Federal Emergency Management Agency · Latest release, retrieved 2026-11-14NRI data and maps
- Air Quality System, annual AQI by county · US Environmental Protection Agency · 2025 dataAirData download files
Derived by Citytistics from the tables above: rent to income (B25064, B19013); home price to income (B25077, B19013).
Survey figures are estimates with margins of error. Formulas and definitions: methodology.
Keep comparing
Other places people weigh against these two, and each one in full.