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☉), approximately 2×1030 kilograms.

In all other galaxies observed to date, the rms velocities are flat, or even falling, toward the center, making it impossible to state with certainty that a supermassive black hole is present.

Such methods, such as broad emission-line reverberation mapping (BLRM), Doppler measurements, velocity dispersion, and the aforementioned M–sigma relation have not yet been well established.

Some objects in this list have two citations, like 3C 273; one from Bradley M. Peterson et al. using the BLRM method,[4] and the other from Charles Nelson using [OIII]λ5007 value and velocity dispersion.

[5] Note that this list is very far from complete, as the Sloan Digital Sky Survey (SDSS) alone detected 200000 quasars, which likely may be the homes of billion-solar-mass black holes.

[15][16] Previous indirect assumptions about the efficiencies of gas accretion and jet power yield a lower limit of 1 billion M☉.

The supermassive black hole at the core of Messier 87 , here shown by an image by the Event Horizon Telescope , is among the black holes in this list.
Comparisons of large and small black holes in galaxy OJ 287 to the Solar System