Queue Counter
Track people joining and leaving.
Tap, click or press Space to keep count.
Tap anywhere inside or press Space
How the Queue Counter Works
The Queue Counter tracks people joining and leaving a line and estimates the wait time from the queue length and the service rate. Tap Join for each arrival and Served for each person who leaves the front of the line.
- Tap Join: Each person joining the line adds 1 to the queue length.
- Tap Served: Each person served lowers the queue length by 1 and counts toward the service rate.
- Watch the service rate: The tool measures people served per minute over the last 10 minutes.
- Read the wait estimate: The tool divides queue length by service rate to estimate the wait.
Queue Counter Formula
The Queue Counter wait estimate equals the queue length divided by the service rate. This relationship comes from Little's law.
- Joined
- People who joined the line
- Served
- People who left after service
- Service rate
- People served per minute
Example: A line has 24 people, and staff serve 3 people per minute. Wait = 24 ÷ 3 = 8 minutes.
Queue Counter Reference Table
The Queue Counter conversion table shows estimated wait times for queue lengths and service rates.
| Queue length | 1 served/min | 2 served/min | 4 served/min | 6 served/min |
|---|---|---|---|---|
| 5 | 5 min | 2.5 min | 1.3 min | 0.8 min |
| 10 | 10 min | 5 min | 2.5 min | 1.7 min |
| 20 | 20 min | 10 min | 5 min | 3.3 min |
| 40 | 40 min | 20 min | 10 min | 6.7 min |
| 60 | 60 min | 30 min | 15 min | 10 min |
About the Queue Counter
A Queue Counter is a two-button tool that measures line length and service speed to estimate waiting time.
Little's law, from queueing theory, states that the average number in a system equals the arrival rate multiplied by the average time in the system. Rearranged, wait time equals queue length divided by throughput.
Ways to Use the Queue Counter
There are 5 main uses of the Queue Counter, including wait-time signs and staffing decisions.
- Wait-time signs: Staff post an estimated wait at the back of the line.
- Staffing decisions: Managers open another till when the wait passes 10 minutes.
- Event entry: Gate teams measure how fast security checks run.
- Food stalls: Vendors track how many customers they serve per minute.
- Clinic waiting rooms: Reception staff estimate waits for walk-in patients.
Tool Details
- Category
- Crowd & Traffic
- Controls
- Taps and keys
- Input Support
- Touch, Pen, Mouse, Keys
- Offline Ready
- On your device