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Delivery Window Capacity Estimator

The Delivery Window Capacity Estimator estimates how many delivery appointments can fit into a defined operating window when average service time and an operating-efficiency factor are known. It is a simple scheduling-capacity model for docks, crews, or delivery resources serving appointments sequentially.

Operations teams can use the output to test appointment-window length, service-time assumptions, or staffing/resource counts before building a detailed schedule. The model assumes average service time is representative and divides effective available minutes by that average. Travel between appointments, customer-specific restrictions, breaks, overlapping resources, and other constraints must be reflected in the inputs or handled separately.

Inputs

resources
hours
minutes
%
Result
—
Estimated delivery appointments
Raw resource minutes—
Effective minutes—
Average service time—
Whole appointments—

1. Enter parallel resources
Use the number of delivery crews, bays, or resources that can work concurrently.

2. Set the operating window
Enter the usable delivery-window length in hours for the planning period.

3. Estimate average appointment time
Use the average service minutes required per appointment on the same basis as the resources entered.

4. Apply scheduling efficiency
Reduce theoretical time for expected nonproductive gaps using the efficiency percentage.

5. Use whole-appointment capacity
For a conservative schedule, compare demand with the whole-appointment count in the breakdown.

Appointment capacity = Resources × Window hours × 60 × (Efficiency % ÷ 100) ÷ Average minutes per appointment

Where:

  • Parallel delivery resources — entered in resources.
  • Delivery window length — entered in hours.
  • Average minutes per appointment — entered in minutes.
  • Scheduling efficiency — entered in %.

Assumptions: all inputs refer to the same planning period or operating scenario, and the model uses the averages entered rather than forecasting external disruption.

What the result means

The result is the theoretical number of appointments that can be served within the window under the entered average service time and efficiency.

Use the whole-appointment figure for a conservative count of fully completed appointments. Real schedules may require additional gaps for travel, variability, breaks, or customer constraints.

Given:
4 resources; 7.5-hour window; 30 minutes per appointment; 80% efficiency.

Calculation:
Effective minutes = 4 × 7.5 × 60 × 0.80 = 1,440 minutes.
Capacity = 1,440 ÷ 30 = 48 appointments.

Result:
48 appointments.

Interpretation:
With the stated assumptions, the available resource time supports 48 average appointments within the window.

What does scheduling efficiency represent?

It is an aggregate allowance for time that is not productively serving appointments. Avoid using it to duplicate downtime already removed from the window.

Can this model handle two appointments at once?

Yes, by increasing the parallel-resource count when those resources can genuinely serve appointments independently.

Should travel time be included in service minutes?

Include it if each resource must travel between appointments and that travel consumes the same scheduling window.

Why is there a decimal capacity result?

The decimal is theoretical capacity. The whole-appointment line shows how many complete average appointments fit without counting a partial one.

How is this different from delivery-window utilization?

Capacity estimates how many appointments could fit. Utilization compares booked or used capacity with the capacity available.