Parity Bar was a purchasing power parity tool for websites, built by Danny Postma. Purchasing power parity (PPP) compares what the same amount of money buys in different countries; a PPP discount lowers the price for buyers in countries where incomes are lower. The site's slogan was "Not everyone earns a US salary".
A website owner set up a bar in the Parity Bar web app and added its script to the site's pages. On each visit the script looked up the visitor's IP address with the ipify service, asked the Parity Bar API for the matching offer, and filled a message template with the visitor's country, the discount and the coupon code.
In January 2021 it was free for the first 10,000 pageviews, and after that customers made a one-time payment for a pack of pageview credits that did not expire; the December 2022 copy calls it free forever. The site is no longer online; this description comes from Internet Archive copies of paritybar.com from January 2021 and December 2022, the newest copy.