v3.25.3
Label Element Value
Risk/Return: oef_RiskReturnAbstract  
Document Type dei_DocumentType 485BPOS
Document Period End Date dei_DocumentPeriodEndDate Feb. 28, 2025
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 Dec. 10, 2025
Document Effective Date dei_DocumentEffectiveDate Dec. 10, 2025
Entity Investment Company Type dei_EntityInvCompanyType N-1A
Prospectus Date oef_ProspectusDate Dec. 10, 2025
MFS Blended Research Emerging Markets Equity ETF | MFS Blended Research Emerging Markets Equity ETF  
Risk/Return: oef_RiskReturnAbstract  
Trading Symbol dei_TradingSymbol BREE