Document and Entity Information	0 Months Ended
Mar. 06, 2015
Risk/Return:
Document Type	497
Document Period End Date	Mar. 06, 2015
Registrant Name	ALGER FUNDS
Central Index Key	0000003521
Amendment Flag	false
Document Creation Date	Mar. 06, 2015
Document Effective Date	Mar. 06, 2015
Prospectus Date	Mar. 01, 2015
Class A and C Prospectus \| Alger Growth Opportunities Fund \| Alger Growth Opportunities Fund Class A
Risk/Return:
Trading Symbol	AOFAX
Class A and C Prospectus \| Alger Growth Opportunities Fund \| Alger Growth Opportunities Fund Class C
Risk/Return:
Trading Symbol	AOFCX
Class I Prospectus \| Alger Growth Opportunities Fund \| Alger Growth Opportunities Fund Class I
Risk/Return:
Trading Symbol	AOFIX
Class Z Prospectus \| Alger Growth Opportunities Fund \| Alger Growth Opportunities Fund Class Z
Risk/Return:
Trading Symbol	AGOZX

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The date the document was made available and submitted, in CCYY-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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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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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