v3.25.2

Cover	Aug. 06, 2025
Document Type	8-K
Amendment Flag	false
Document Period End Date	Aug. 06, 2025
Entity File Number	001-42700
Entity Registrant Name	BEST SPAC I Acquisition Corp.
Entity Central Index Key	0002051587
Entity Tax Identification Number	00-0000000
Entity Incorporation, State or Country Code	D8
Entity Address, Address Line One	701, 7/Floor
Entity Address, Address Line Two	United Building
Entity Address, Address Line Three	17-19 Jubilee Street
Entity Address, City or Town	HK
Entity Address, Country	HK
Entity Address, Postal Zip Code	00000
City Area Code	+852
Local Phone Number	9828 3397
Written Communications	false
Soliciting Material	false
Pre-commencement Tender Offer	false
Pre-commencement Issuer Tender Offer	false
Entity Emerging Growth Company	true
Elected Not To Use the Extended Transition Period	false
Units, each consisting of one Class A ordinary share, with no par value, and one right to receive one-tenth of one Class A ordinary share
Title of 12(b) Security	Units, each consisting of one Class A ordinary share, with no par value, and one right to receive one-tenth of one Class A ordinary share
Trading Symbol	BSAAU
Security Exchange Name	NASDAQ
Class A ordinary shares, with no par value
Title of 12(b) Security	Class A ordinary shares, with no par value
Trading Symbol	BSAA
Security Exchange Name	NASDAQ
Rights [Member]
Title of 12(b) Security	Rights
Trading Symbol	BSAAR
Security Exchange Name	NASDAQ

Boolean flag that is true when the XBRL content amends previously-filed or accepted submission.

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Area code of city

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For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period. The format of the date is YYYY-MM-DD.

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The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.

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Address Line 1 such as Attn, Building Name, Street Name

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Address Line 2 such as Street or Suite number

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Address Line 3 such as an Office Park

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Name of the City or Town

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ISO 3166-1 alpha-2 country code.

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Code for the postal or zip code

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A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Indicate if registrant meets the emerging growth company criteria.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Indicate if an emerging growth company has elected not to use the extended transition period for complying with any new or revised financial accounting standards.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.

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Two-character EDGAR code representing the state or country of incorporation.

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The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Exchange Act
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The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Local phone number for entity.

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Title of a 12(b) registered security.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Name of the Exchange on which a security is registered.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as soliciting material pursuant to Rule 14a-12 under the Exchange Act.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Exchange Act
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Trading symbol of an instrument as listed on an exchange.

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as written communications pursuant to Rule 425 under the Securities Act.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Securities Act
-Number 230
-Section 425

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BEST SPAC I Acquisition Corp. 8-K