Annual report pursuant to Section 13 and 15(d)

Document and Entity Information Document

Document and Entity Information Document - USD ($)
12 Months Ended
Dec. 31, 2018
Feb. 01, 2019
Jun. 29, 2018
Document and Entity Information [Abstract]      
Entity Registrant Name Redfin Corp    
Entity Central Index Key 0001382821    
Current Fiscal Year End Date --12-31    
Entity Filer Category Large Accelerated Filer    
Document Type 10-K    
Document Period End Date Dec. 31, 2018    
Document Fiscal Year Focus 2018    
Document Fiscal Period Focus FY    
Amendment Flag false    
Entity Voluntary Filers No    
Entity Well Known Seasoned Issuer Yes    
Entity Current Reporting Status Yes    
Entity Common Stock, Shares Outstanding   90,488,242  
Entity Public Float     $ 1,755,832,823