v3.25.1
Cover
Jun. 05, 2025
Cover [Abstract]  
Document Type 8-K
Amendment Flag false
Document Period End Date Jun. 05, 2025
Entity File Number 0-018655
Entity Registrant Name Exponent, Inc.
Entity Central Index Key 0000851520
Entity Tax Identification Number 77-0218904
Entity Incorporation, State or Country Code DE
Entity Address, Address Line One 149 Commonwealth Drive
Entity Address, City or Town Menlo Park
Entity Address, State or Province CA
Entity Address, Postal Zip Code 94025
City Area Code (650)
Local Phone Number 326-9400
Written Communications false
Soliciting Material false
Pre-commencement Tender Offer false
Pre-commencement Issuer Tender Offer false
Title of 12(b) Security Common Stock, par value $0.001 per share
Trading Symbol EXPO
Security Exchange Name NASDAQ
Entity Emerging Growth Company false