City comparison
Diamond Bar, CA is about 30 miles (50 km) from Rancho Santa Margarita, CA in a straight line. By road, the drive is roughly 40 miles, or about 36 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 Rancho Santa Margarita, CA takes about 3 min, covering roughly 30 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.
Diamond Bar has a population of 54,534, vs 47,702 in Rancho Santa Margarita — about 1.1× larger by population. By land area, Diamond Bar covers about 15 sq mi vs 13 sq mi for Rancho Santa Margarita.
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 | Rancho Santa Margarita | Difference |
|---|---|---|---|
| Median rent | $2,332/mo | $2,441/mo | 4.7% higher in Rancho Santa Margarita |
| Median home value | $829,000 | $861,100 | 3.9% higher in Rancho Santa Margarita |
| Median household income | $106,881 | $150,146 | 40.5% higher in Rancho Santa Margarita |
| 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 $100,232 in Rancho Santa Margarita to maintain your standard of living.
Climate, safety, and demographics side by side.
Diamond Bar and Rancho Santa Margarita have nearly identical overall cost-of-living indices. If you earn $80,000 in Diamond Bar, you'd need about $80,186 in Rancho Santa Margarita to keep the same standard of living.