Cover - $ / shares	1 Months Ended
	Jun. 30, 2025	Oct. 23, 2025
Document Type	10-Q
Amendment Flag	false
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Jun. 30, 2025
Document Fiscal Period Focus	Q2
Document Fiscal Year Focus	2025
Current Fiscal Year End Date	--12-31
Entity File Number	001-42837
Entity Registrant Name	OTG Acquisition Corp. I
Entity Central Index Key	0002077010
Entity Tax Identification Number	98-1868600
Entity Incorporation, State or Country Code	E9
Entity Address, Address Line One	12003 Cielo Court
Entity Address, City or Town	Palm Beach Gardens
Entity Address, State or Province	FL
Entity Address, Postal Zip Code	33418
City Area Code	(917)
Local Phone Number	488-5629
Entity Current Reporting Status	No
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Elected Not To Use the Extended Transition Period	false
Entity Shell Company	true
Entity Information, Former Legal or Registered Name	Not Applicable
Units, each consisting of one Class A ordinary share, $0.0001 par value per share, and one-half of one redeemable warrant
Title of 12(b) Security	Units, each consisting of one Class A ordinary share, $0.0001 par value per share, and one-half of one redeemable warrant
Trading Symbol	OTGAU
Security Exchange Name	NASDAQ
Class A Ordinary Shares [Member]
Title of 12(b) Security	Class A ordinary shares included as part of the units
Trading Symbol	OTGA
Security Exchange Name	NASDAQ
Redeemable warrants included as part of the units, each whole warrant exercisable for one Class A ordinary share at an exercise price of $11.50
Title of 12(b) Security	Redeemable warrants included as part of the units, each whole warrant exercisable for one Class A ordinary share at an exercise price of $11.50
Trading Symbol	OTGAW
Security Exchange Name	NASDAQ
Common Class A [Member]
Entity Common Stock, Shares Outstanding		23,775,000
Entity Listing, Par Value Per Share	$ 0.0001
Common Class B [Member]
Entity Common Stock, Shares Outstanding		5,750,000
Entity Listing, Par Value Per Share	$ 0.0001