Document and Entity Information	Total
Prospectus:
Document Type	497
Document Period End Date	Nov. 01, 2022
Entity Registrant Name	BNY MELLON CALIFORNIA AMT-FREE MUNICIPAL BOND FUND, INC.
Entity Central Index Key	0000720064
Entity Inv Company Type	N-1A
Amendment Flag	false
Document Creation Date	Nov. 01, 2022
Document Effective Date	Nov. 01, 2022
Prospectus Date	Sep. 30, 2022
BNY MELLON CALIFORNIA AMT-FREE MUNICIPAL BOND FUND, INC. \| Class Z
Prospectus:
Trading Symbol	DRCAX
BNY MELLON CALIFORNIA AMT-FREE MUNICIPAL BOND FUND, INC. \| Class C
Prospectus:
Trading Symbol	DCACX
BNY MELLON CALIFORNIA AMT-FREE MUNICIPAL BOND FUND, INC. \| Class A
Prospectus:
Trading Symbol	DCAAX
BNY MELLON CALIFORNIA AMT-FREE MUNICIPAL BOND FUND, INC. \| Class I
Prospectus:
Trading Symbol	DCMIX
BNY MELLON CALIFORNIA AMT-FREE MUNICIPAL BOND FUND, INC. \| Class Y
Prospectus:
Trading Symbol	DCAYX

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The date the document was made available and submitted, in YYYY-MM-DD format. The date of submission, date of acceptance by the recipient, and the document effective date are all potentially different.

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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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