Popular Online PayPal Fee Calculators Are Wrong
Thursday, September 16, 2010 (06:14:36)

Posted by Devon

While developing our own in house PayPal module we came across an odd sort of mass miscalculation happening online.

PayPal Fee Calculators using incorrect calculations:

The correct PayPal fee as of this date is (* 2.9% + .30).
The sites listed above use the calculation (+.30 * 2.9%) which of course yields a must different and ultimately incorrect result.

Because those 2 sites are the most visited sites for search keywords "PayPal Fee Calculator" they are unwittingly affecting thousands of people (or more). There are a lot of people sending more money than required for their purchases. This of course nets PayPal more money. Unfortunately there isn't any information online currently which describes the mistake (other than here).

This news is important to other web developers looking to make their own PayPal fee calculators and browsing for other general examples online. If one assumes the calculations on those sites are correct it makes PayPal look to be skimming money (more specifically each half or hundredth cent depending on decimal placement) from all customers. This is not the case and could potentially affect PayPal's reputation as a credible company. PayPal does indeed stick to the correct calculation they advertise.

To all developers out there; your calculations are correct and the sites listed above are incorrect. Don't waste precious time trying to debug your fee calculation scripts because you'll never solve the fictitious issue of the missing half cents. Wink

PayPal Fee Calculators using correct calculations:

The module we're building here will have a fee calculator built in and does use the correct calculation (as currently stipulated by PayPal). PayPal does change their rate from time to time so in the future developers will have to adjust their scripts accordingly.

Content received from: Treasure Coast Designs, http://www.treasurecoastdesigns.com