Cover Page - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Mar. 08, 2024	Jun. 30, 2023
Entity Listings [Line Items]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2023
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity Registrant Name	Cepton, Inc.
Entity Incorporation, State or Country Code	DE
Entity File Number	001-39959
Entity Tax Identification Number	27-2447291
Entity Address, Address Line One	399 West Trimble Road
Entity Address, City or Town	San Jose
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	95131
City Area Code	408
Local Phone Number	459-7579
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
ICFR Auditor Attestation Flag	false
Entity Shell Company	false
Entity Public Float			$ 40.8
Entity Common Stock, Shares Outstanding		15,920,917
Entity Central Index Key	0001498233
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Amendment Flag	false
Document Financial Statement Error Correction [Flag]	false
Common stock, par value $0.00001 per share
Entity Listings [Line Items]
Title of 12(b) Security	Common stock, par value $0.00001 per share
Trading Symbol	CPTN
Security Exchange Name	NASDAQ
Redeemable warrants, exercisable for common stock at an exercise price of $11.50 per share, subject to adjustment
Entity Listings [Line Items]
Title of 12(b) Security	Redeemable warrants, exercisable for common stock at an exercise price of $115.00 per share, subject to adjustment
Trading Symbol	CPTNW
Security Exchange Name	NASDAQ