Annual report pursuant to Section 13 and 15(d)

Document and Entity Information

Document and Entity Information (USD $)
12 Months Ended
Dec. 31, 2013
Jun. 30, 2013
Document and Entity Information [Abstract]    
Entity Registrant Name STAMPS.COM INC  
Entity Central Index Key 0001082923  
Current Fiscal Year End Date --12-31  
Entity Well-known Seasoned Issuer No  
Entity Voluntary Filers No  
Entity Current Reporting Status Yes  
Entity Filer Category Accelerated Filer  
Entity Public Float   $ 0
Entity Common Stock, Shares Outstanding 0  
Document Fiscal Year Focus 2013  
Document Fiscal Period Focus FY  
Document Type 10-K  
Amendment Flag false  
Document Period End Date Dec. 31, 2013