Cover Page	9 Months Ended
Dec. 31, 2024
Cover [Abstract]
Document Type	6-K
Entity Central Index Key	0001973239
Entity Registrant Name	ARM HOLDINGS PLC /UK
Current Fiscal Year End Date	--03-31
Document Period End Date	Dec. 31, 2024
Document Fiscal Year End Focus	2025
Document Fiscal Period Focus	Q3
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Cover page.

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End date of current fiscal year in the format --MM-DD.

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This is focus fiscal year of the document report in YYYY format. For a 2006 annual report, which may also provide financial information from prior periods, fiscal 2006 should be given as the fiscal year focus. Example: 2006.

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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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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
-Publisher SEC
-Name Exchange Act
-Number 240
-Section 12
-Subsection b-2

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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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