Somehow PriceTracker does not update prices any more. What’s going on?

On March 9, 2020 Amazon made significant changes to its Product Advertising API which resulted in PriceTracker not being able to retrieve product information any more. The effort to rewrite the application is very significant, so unfortunately we had to discontinue support for this application.

What’s this ASIN thing?

All items for sale on have identifiers. The ASIN (Amazon Standard Item Number) is an alphanumeric token that uniquely identifies items in the Amazon marketplace. All items in the marketplace have an ASIN. 

The ISBN-10 (International Standard Book Number) is an alphanumeric token that uniquely identifies a book. The “-10” is a 10-character version of the ISBN.

The ASIN or ISBN-10 are the way PriceTracker for Amazon queries the Amazon API to retrieve item information.

Where can I find the ASIN or ISBN-10?

The ASIN is included in the Amazon URL. Please see the following examples:

As of version 1.0.10, PriceTracker allows you to paste the Amazon item URL directly into the application to add an item to your list (in addition to entering the ASIN/ISBN).

For books, when you’re looking at an item detail page on, scroll down to the section called “Item Details”. There you’ll be able to find the ISBN-10 (for books).

Additional examples (click to zoom):

ASIN and ISBN-10 illustration

PriceTracker added my item, but there’s no price – why?

For some items, the Amazon API (application programming interface, a public way to retrieve information from Amazon) provides general item information, but no prices. In these case, the item will be added to PriceTracker, but without a price. Every time you refresh prices, PriceTracker will continue to attempt to retrieve a price in case it becomes available later.

Sometimes PriceTracker doesn’t seem to update prices – is that a bug?

Long story. Amazon is providing an API to retrieve item pricing and other information. Unfortunately, one has to “earn” transactions via the API by people purchasing tracked items. Otherwise Amazon may temporarily limit or throttle access. So if too many people just track items, but don’t purchase anything, PriceTracker may temporarily not be allowed to retrieve pricing (or access is limited to a few transactions). This is unfortunately out of my control and part of how Amazon is choosing to manage their API. You can help by purchasing items tracked via PriceTracker.

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