Which is more accurate: Zillow’s Zestimate or Redfin’s Estimate?

Accuracy matters a lot in this arena because many buyers and sellers use the online estimates to price their homes or make purchase offers, literally handing sellers or buyers the estimates as part of their bargaining strategy. This is despite both companies’ warnings that these are not appraisals, only algorithm-based computer estimates. 

https://www.washingtonpost.com/realestate/which-firm-has-more-accurate-online-estimates-for-homes-zillow-or-redfin/2019/02/19/7a1f6436-346b-11e9-a400-e481bf264fdc_story.html?noredirect=on&utm_term=.fa43a5688d7b