Skip to main content

Zillow algorithm overestimates Seattle home’s value by 700 percent

Zillow may just be a seller’s best friend (but certainly not a buyer’s). According to a recent report from the Seattle Times, the popular online real estate database somehow managed to overvalue a Seattle home by a whopping 700 percent.

The home, which owners Sue and Roy Carlson purchased in June 2017, cost the couple just $225,000 (a particularly good deal because the property was initially slated for foreclosure). Other real estate companies (think Redfin and Realtor.com), now show the value of the home as somewhere between $268,000 and $318,000. Zillow, on the other hand, says that the property is worth $1.8 million.

Thanks to some serious SEO magic on Zillow’s side, when you Google this home’s address (like most home addresses), it’s the Zillow result (or Zestimate) that returns first. And that means that the first thing that most folks are seeing when they look into the Carlson’s home is a valuation that is seven times what just about everyone else on the market thinks it ought to be.

“I don’t have a clue where they came up with this number,” Sue Carlson told the Seattle Times. “It’s not worth anywhere near $1 million. They’re nuts.” She added, “If anybody wanted to buy the house (and saw the $1.8 million Zestimate), they would just go, ‘Well, that’s ridiculous.’”

Carlson then took a deep dive to determine exactly how Zillow might’ve arrived at its hugely inflated figure, and as the Times notes, “Her story offers a peek into how algorithms can go wrong, and highlights an ongoing issue with one of Seattle-based Zillow’s most popular features.”

As it turns out, Zillow admitted in 2017 that its Zestimates are generally off by around $40,000 when considering the “typical single-family home sold in Seattle.” In fact, when the company’s own CEO Spencer Rascoff sold his own house in 2016, the Zestimate was too high by a factor of 40 percent. Moreover, the house he ultimately purchased was misestimated by more than $1 million.

 These issues have led to some lawsuits, as well as a number of attempts by Zillow to improve its estimation process. In fact, the company last year launched a competition with $1 million prize in prize money to better the Zestimate algorithm (the company recently announced 100 semifinalists who have already made some small improvements to the platform).

The case of the Carlson’s home, however, is particularly outlandish. The problem was that Zillow somehow recorded the actual sale price of the home when the Carlsons bought it as $1.77 million. This, a spokesperson said, was not a fault of Zillow’s, but rather of a third-party vendor who incorrectly supplied sales data. Zillow has since fixed the actual sale price, and the Zestimate should soon be corrected as well.

“Overall, the Zestimate is incredibly accurate — with a median error rate of 4.5 percent — but occasionally human error does occur,” Zillow spokesman Viet Shelton said in a statement. “Since the Zestimate is calculated using thousands of data points, it’s only as good as the data provided.”

Lulu Chang
Former Digital Trends Contributor
Fascinated by the effects of technology on human interaction, Lulu believes that if her parents can use your new app…
Eve MotionBlinds Upgrade Kit and Blinds Collection join the Matter lineup
The Eve MotionBlinds Upgrade Kit being installed.

Eve is a prominent name in the smart home world, with the company responsible for a variety of devices covering everything from smart plugs and security cameras to smart light switches and motion sensors. Its catalog is growing even more enticing today, with the Eve Blinds Collection and MotionBlinds Upgrade Kit gaining Matter support.

The MotionBlinds Upgrade Kit will likely appeal to more customers, as it costs just $200 and works with most existing setups. Installation is as simple as removing your shades, placing the MotionBlinds Upgrade Kit through the roller rod, then reinstalling the unit on your windows. Blinds with a roller between 1.5 inches and 2.0 inches are compatible with the upgrade kit.

Read more
Philips Hue lights have a rare discount, but there’s a catch
A TV with ambient backlighting from Philips Hue.

One of the cool things about Philips Hue lighting is how much freedom it gives you over creating the perfect ambiance in your home. One of the cool things about buying Philips Hue products over at Best Buy right now is how much freedom Best Buy is giving you over what you buy to save money. Right now, when you buy two or more select Philips Hue smart lighting product in Best Buy's offer builder, you can save 15%. Tap the button below to start building your own bundle and see all of the products available. While they don't include the best smart light bulbs that Philips produces, you'll be amazed by the versatility of the lightstrips. Or keep reading for an overview of some of the top picks from the bundle.

What you should purchase from the Philips Hue offer builder
The place to start with this deal is the and the if you don't already have them. These are the devices that take your movies, music, and games and syncs them to your lights.

Read more
Samsung’s futuristic Jet Bot AI+ robot vacuum is $400 off
The Samsung Jet Bot AI+ Robot Vacuum cleaning the floor.

For families who need a lot of help in keeping their floors spotless, the Samsung Jet Bot AI+ is an investment that you'll want to make. It's pretty expensive at its original price of $1,300, but a $400 discount from Samsung pulls it down to $900. It's still not cheap, but this futuristic robot vacuum could be the only device that you need to keep dirt, debris, and pet hair away from your sight. You're going to have to complete your purchase for it as soon as possible though, as there's no telling when the offer expires.

Why you should buy the Samsung Jet Bot AI+ robot vacuum
The Samsung Jet Bot AI+ checks all the boxes in the features that are recommended by our guide on how to choose a robot vacuum. It's equipped with powerful sensors and object recognition technology that allows it to avoid furniture when it's cleaning your floors, while LiDAR technology allows it to create accurate maps of the rooms in your home so that it can properly navigate and clean more efficiently. The robot vacuum also features a five-layer filtration system that allows it to release clean air, and when it's done, it goes back to its Clean Station where it empties its contents.

Read more