National Archives Database (NAD) publishes information about archives and archival holdings at the Swedish National Archives, municipal and regional archives, archives of popular movements and associations, trade and industry and archives of museums and libraries etc
You can also find contact information for Swedish archival institutions in the tab Search archival institutions. You can find supplementary databases on topographical division and historicall accounts of public administrations in the tab Search places
Several institutions publish archival inventories in NAD together with other finding aids.