Flight Time from Boulder to Thornton
The flight from Boulder to Thornton covers about 19 mi and takes roughly 32 min nonstop. Flight duration estimate and fare guide.
32 min
Nonstop flight
19 mi
Straight-line
26 mi
By road
32 min
Flight time
Boulder and Thornton are about 19 mi (30 km) apart in a straight line. By road that works out to roughly 26 mi (42 km), a drive of about 36 min. A nonstop flight covers the great-circle distance in approximately 32 min.
| Straight-line distance | 19 mi / 30 km |
| Road distance (est.) | 26 mi / 42 km |
| Driving time (est.) | 36 min |
| Nonstop flight (est.) | 32 min |
| Driving fuel (est., 1-way) | $3 |
| Typical flight fare | $80–$250 |
| Geographic midpoint | 39.942, -105.121 |
How these estimates work
Straight-line distance uses the haversine formula on each city's coordinates. Road distance applies a circuity factor (~1.2–1.4×) and driving time a blended average speed. Flight time uses typical jet cruise speed plus ~30 minutes for taxi, climb and descent. Treat all figures as planning estimates.
Frequently asked questions
Boulder to Thornton is about 19 mi (30 km) in a straight line, and roughly 26 mi (42 km) by road.