# Reorder Point & Quantity Calculator

Use lead time demand, safety stock and stock already on order in a constant demand plan.

[Open this tool](https://whatson.pk/reorder-calculator/)

Category: Seller Pricing & Profit

A reorder trigger and the size of the next order are related but different questions.

Enter daily demand, supplier lead time and safety stock. Include stock already on order when comparing inventory position with the refill target.

## Inputs and controls

* Average units sold per day (units/day). Allowed range: 0 to 1000000
* Supplier lead time (days). Allowed range: 0 to 3660
* Safety stock (units). Allowed range: 0 to 1000000
* Coverage after arrival (days). Allowed range: 0 to 3660
* On hand units (units). Allowed range: 0 to 1000000
* Units already on order (units). Allowed range: 0 to 1000000
* Reserved units (units). Allowed range: 0 to 1000000

## How to use

* Enter average units sold per day, supplier lead time, safety stock and coverage after arrival.

* Enter on hand units, units already on order and reserved units.

* Select Calculate result. Read the returned values alongside the assumptions below before copying, exporting or acting on the result.


## Why use this tool

Separating trigger and replenishment quantity helps avoid ordering the target stock amount on top of inventory already committed.


## Before relying on the result

Order up to target is average demand × (lead time + after arrival coverage) plus safety stock. This constant demand model does not optimise MOQ, forecast seasonality or guarantee availability.


## Tool limitations

Order up to target is average demand × (lead time + after arrival coverage) plus safety stock. This constant demand model does not optimise MOQ, forecast seasonality or guarantee availability.

## Questions

### Does this forecast seasonal demand?

No. It uses constant entered demand. Change the assumptions when expected sales or supplier delays change.

### What should I check before using Reorder Point & Quantity Calculator?

Check Average units sold per day, Supplier lead time, Safety stock and Coverage after arrival. Use the exact units shown beside the controls and replace any example values with your own inputs.

Source page last modified (UTC): 2026-10-01T18:05:21+00:00

This profile describes the tool. It does not execute it or supply a professional certification.