Roundabout Capacity Calculator
Calculate entry capacity, volume-to-capacity ratio, delay, and level of service for single and multi-lane roundabouts using HCM methodology.
Inputs
veh/hr
ft
ft
°
Results
Entry Capacity (per lane)
685 veh/hr
Level of Service
B
Total Entry Capacity685 veh/hr
V/C Ratio0.44
Control Delay14.3 sec/veh
95th % Queue (est.)156 ft
How to Use This Calculator
- Enter Entry Lanes, 1 Lane, and 2 Lanes.
- Set Circulating Lanes, 1 Lane, and 2 Lanes.
- Adjust Conflicting Circulating Flow, Entry Width as needed.
- Review Entry Capacity (per lane) (veh/hr) and Level of Service.
- Use Total Entry Capacity (veh/hr) and V/C Ratio to inform your decision.
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