v3.26.1
Label Element Value
Risk/Return: oef_RiskReturnAbstract  
Document Type dei_DocumentType 485BPOS
Document Period End Date dei_DocumentPeriodEndDate Feb. 28, 2026
Registrant Name dei_EntityRegistrantName MFS® ACTIVE EXCHANGE TRADED FUNDS TRUST
Entity Central Index Key dei_EntityCentralIndexKey 0002018846
Amendment Flag dei_AmendmentFlag false
Document Creation Date dei_DocumentCreationDate May 18, 2026
Document Effective Date dei_DocumentEffectiveDate May 19, 2026
Entity Investment Company Type dei_EntityInvCompanyType N-1A
Prospectus Date oef_ProspectusDate May 19, 2026
MFS Active International Value ETF | MFS Active International Value ETF  
Risk/Return: oef_RiskReturnAbstract  
Trading Symbol dei_TradingSymbol MIVL
MFS Blended Research Small-Mid Cap ETF | MFS Blended Research Small-Mid Cap ETF  
Risk/Return: oef_RiskReturnAbstract  
Trading Symbol dei_TradingSymbol BRSM