Wikileaf, also known as the Priceline of pot, allows medical marijuana patients to compare pot costs at 1,100 dispensaries in six states.
Website founder Dan Nelson, a financial blogger, said he was inspired by the interest rate comparison model for banks.
"I thought the same dynamic could be applied to the medical and legal marijuana businesses," Nelson told USA TODAY Network.
Wikileaf users set the amount of money they want to pay and how many miles they are willing to travel for their weed. Marijuana patients won't be able to order the marijuana online, so they'll have to go to the dispensary.
Users can limit their search by marijuana strain. Afghan Kush, for example, is described as 95% of the indica strain and 5% of the sativa strain.
A lot of dispensaries have only a "bare-bones" website, and marijuana businesses are barred from advertising on Facebook and Twitter, said Taylor West, spokeswoman for the National Cannabis Industry Association.
"If you try to get the paid promotion, it will often get flagged as inappropriate content," West said.
Nelson said his site is different from Leafly and Weedmaps, which are focused on user ratings.
Nelson, a medical marijuana patient in Seattle, said his site, which was launched in January, is the first to offer price comparisons.
"I'd go to a dispensary that offered me a strain for this amount of money, and I'd walk two blocks down, and a dispensary would offer me twice as much for the same amount of money," Nelson said.
In the USA, 22 states and D.C. have legalized medical marijuana. Wikileaf lists dispensaries in Arizona, California, Colorado, Nevada, Oregon and Washington.
As Seattle's retail market is set to open next month, Nelson said the site will include recreational pot price comparisons, and those pages will have a different look from the medical comparisons. Only Washington and Colorado have legalized recreational marijuana.
Dispensaries can be listed for free, but Nelson said the site will start charging businesses in 2016.
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