v3.25.2
Cover Page - shares
 6 Months Ended
Jun. 29, 2025
Jul. 27, 2025
Cover [Abstract]    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Jun. 29, 2025  
Document Transition Report false  
Entity File Number 001-36104  
Entity Registrant Name Potbelly Corporation  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 36-4466837  
Entity Address, Address Line One 500 W Madison St  
Entity Address, Address Line Two Suite 1000  
Entity Address, City or Town Chicago  
Entity Address, State or Province IL  
Entity Address, Postal Zip Code 60606  
City Area Code 312  
Local Phone Number 951-0600  
Title of 12(b) Security Common Stock, $0.01 par value  
Trading Symbol PBPB  
Security Exchange Name NASDAQ  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   30,260,672
Entity Central Index Key 0001195734  
Document Fiscal Year Focus 2025  
Current Fiscal Year End Date --12-28  
Document Fiscal Period Focus Q2  
Amendment Flag false