City comparison
Diamond Bar, CA is about 20 miles (30 km) from Fountain Valley, CA in a straight line. By road, the drive is roughly 30 miles, or about 27 min behind the wheel at highway speeds.
Driving distance is a rough estimate (great-circle × 1.25); driving time assumes a 60 mph blended average. Real trips run 10–20% longer with stops.
A direct flight from Diamond Bar, CA to Fountain Valley, CA takes about 3 min, covering roughly 20 miles in a straight line. Connecting itineraries with a layover typically add 1–3 hours.
Block-to-block estimate at ~500 mph cruise, including taxi, climb, and descent — what an airline would publish, not pure airborne time.
Fountain Valley has a population of 56,754, vs 54,534 in Diamond Bar — about the same size. By land area, Diamond Bar covers about 15 sq mi vs 9.1 sq mi for Fountain Valley.
Population from US Census ACS. Land area from the Census Gazetteer (city proper, excluding inland water).
Cost indices by category, with the US city average (100) marked.
Index: 100 = US city average. Lower is more affordable.
Side-by-side costs, salaries, and sub-category indices.
| Metric | Diamond Bar | Fountain Valley | Difference |
|---|---|---|---|
| Median rent | $2,332/mo | $2,412/mo | 3.4% higher in Fountain Valley |
| Median home value | $829,000 | $932,800 | 12.5% higher in Fountain Valley |
| Median household income | $106,881 | $108,860 | 1.9% higher in Fountain Valley |
| Groceries index | 106.4 | 106.4 | ≈ equal |
| Utilities index | 155.6 | 155.6 | ≈ equal |
| Transportation index | 104.4 | 104.4 | ≈ equal |
| Healthcare index | 104.3 | 104.3 | ≈ equal |
How much you'd need to earn in the other city to keep the same standard of living.
If you earn $100,000 in Diamond Bar, you'd need $100,167 in Fountain Valley to maintain your standard of living.
Climate, safety, and demographics side by side.
Diamond Bar and Fountain Valley have nearly identical overall cost-of-living indices. If you earn $80,000 in Diamond Bar, you'd need about $80,134 in Fountain Valley to keep the same standard of living.