---
title: "Prorating Example"
slug: "prorating-example"
updated: 2026-08-10T20:23:05Z
published: 2026-08-10T20:23:05Z
canonical: "help.idibilling.com/prorating-example"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://help.idibilling.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Prorating Example

Prorating is based on the percentage of the current bill period that the product has been in service.

- Product proration type is In Advance.
- Product service start date is 02/23/99.
- Monthly charge is $12.12.
- Bill period start date is 03/1/99.
- Bill period end date is 04/1/99 (this is the start date of the next bill period).

The percentage is calculated using the following numbers:

***Duration Used***

The duration of the product, in seconds, from the product service start date to the bill period end date.
- From 02/23/99 up to, but not including, 04/1/99. The Duration Used = 3,196,800 seconds.

***Duration Per Cycle***

The duration per cycle is the duration, in seconds, from the bill period start date to the bill period end date.
- From 03/1/99 up to, but not including, 04/1/99. The Duration Per Cycle = 2,678,400 seconds.

***Percentage***

The percentage is the Duration Used divided by the Duration Per Cycle, plus 1 (add 1 to the results of the division, because the product is prorated in-advance).
- (3,196,800 seconds ¸ 2,678,400 seconds) + 1 = 2.19 %.