- Enter usable stock. Count only product that can actually be used for upcoming services.
- Enter average use per service. Use the same unit as the stock figure.
- Enter daily service volume. Use a realistic average rather than the busiest possible day.
- Enter working days per week. This converts working days of supply into working weeks.
- Review the runout estimate. The main result shows working days supported at the modeled usage rate.
Hair Extension Product Duration Estimator
The Hair Extension Product Duration Estimator estimates how long the current hair extension inventory supply will last at the entered usage rate. It connects inventory quantity to average consumption per service and planned service volume, which is useful for reorder timing, purchasing checks, and avoiding stockouts during a busy schedule.
The main result is expressed in working days, with supporting service count and working weeks. Because real usage varies by client, technique, waste, and partial packages, use an average that reflects your recent operating pattern rather than a theoretical minimum dose.
Inputs
packs
packs
services
days
Result
—
The main value estimates the number of working days the current stock can support.
Services supported—
Working weeks—
Average daily use—
Starting stock—
Services supported = Usable stock ÷ Average use per service
Working days of supply = Services supported ÷ Services per working day
Working weeks of supply = Working days of supply ÷ Working days per week
Stock and per-service use must use the same unit. The estimate assumes average usage and service volume remain stable.
What the result means
The main value estimates the number of working days the current stock can support.
Actual duration changes with service mix, waste, and day-to-day volume.
An extension studio has 96 install packs available. A typical full installation uses 4 packs, and the studio completes about 6 installations per working day-equivalent across a 5-day schedule.
Given: stock 96, use 4 per service, 6 services per working day, 5 working days per week.
Calculation: Services supported = 96 ÷ 4 = 24.00. Working days = 24.00 ÷ 6 = 4.00. Working weeks = 4.00 ÷ 5 = 0.80.
Result: The current stock supports about 4.0 working days at the modeled rate.
Given: stock 96, use 4 per service, 6 services per working day, 5 working days per week.
Calculation: Services supported = 96 ÷ 4 = 24.00. Working days = 24.00 ÷ 6 = 4.00. Working weeks = 4.00 ÷ 5 = 0.80.
Result: The current stock supports about 4.0 working days at the modeled rate.
Should I enter unopened stock or usable stock?
Use the amount you reasonably expect to be available for upcoming services. Exclude damaged, expired, reserved, or otherwise unavailable inventory if it cannot support normal appointments.
What unit should I use?
Any consistent quantity unit works. Stock and average use per service must use the same unit, such as grams with grams, milliliters with milliliters, or packs with packs.
Why can the services-supported result include a fraction?
The mathematical ratio can end with partial product remaining. In practice, a full service may require enough stock for the complete average amount, so operational planning may use the next lower whole service.
How should I handle variable usage between clients?
Enter a recent average that includes your normal mix of lighter and heavier usage. If variability is large, also test a higher-use scenario to create a reorder buffer.
Does this estimate include delivery lead time?
No. It estimates consumption duration only. Compare the projected runout point with supplier lead time and your desired safety stock when deciding when to reorder.