List of most massive black holes

This is an ordered list of the most massive black holes so far discovered (and probable candidates), measured in units of solar masses (M☉), about 2×1030 kilograms. == Introduction == A supermassive black hole (SMBH) is an extremely large black hole, on the order of at least hundreds of thousands of solar masses (M☉), and is theorized to exist in the center of almost all massive galaxies.