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Top 10 Most Massive Black Holes in the Universe by Mass

The ten most massive black holes ever found, ranked by estimated mass in billions of solar masses.

Updated September 21, 2026 10 ranked 7 sources

Quick answer

Phoenix A is the most massive known black hole, at an estimated 100 billion solar masses, although a 2024 study put it as low as 12.6 billion. IC 1101 is second at 97.7 billion and 4C +74.13 third at 51.3 billion. The ranking uses the primary mass estimate in Wikipedia's List of most massive black holes as of 21 September 2026; all figures are model-dependent estimates.

Every large galaxy appears to hide a supermassive black hole at its center, but only a handful have grown to truly monstrous proportions. The objects below are the heavyweight champions — black holes whose masses are measured in tens of billions of Suns. Black hole masses can't be weighed directly. Every figure here is a model-dependent estimate, and astronomers revise them as measurement techniques improve. This list ranks them by the best current published estimate for each object.

Mass (billion solar masses)

Mass (billion solar masses)
Phoenix A
100 billion solar masses
IC 1101
97.7 billion solar masses
4C +74.13
51.3 billion solar masses
TON 618
40.7 billion solar masses
SDSS 143148.09+053558
36.4 billion solar masses
SDSS J114833.14+193003.2
36.3 billion solar masses
NGC 3842
34.6 billion solar masses
SMSS J215728.21-360215.1
34 billion solar masses
SDSS J102325.31+514251.0
33.1 billion solar masses
Abell 1201 BCG
32.7 billion solar masses

The ranking

1

Phoenix A

The current record holder at an estimated 100 billion solar masses — more than the mass of all the stars in the Milky Way combined. Its mass has not been measured directly, and a later study suggested it could be as low as 12.6 billion, so this figure is actively debated.

Host / setting: Brightest galaxy of the Phoenix Cluster (SPT-CLJ2344-4243), about 5.8 billion light-years awayMass-estimate method: Calorimetric model of adiabatic core regrowth (indirect); not measured directlyNotable: Current record holder; a 2024 study gave a competing estimate of ~12.6 billion solar masses
2

IC 1101

The black hole at the heart of one of the largest known galaxies. Its estimated mass of 97.7 billion solar masses comes with an enormous uncertainty range — the upper bound would make it the largest by far.

Host / setting: Center of the Abell 2029 galaxy cluster; host is one of the largest known galaxies, about 1.7 million light-years acrossMass-estimate method: Break radius of the central core; 9.77 (+17.14 / -6.22) x 10^10 M☉Notable: Uncertainty range spans ~35 to ~270 billion solar masses
3

4C +74.13

A radio galaxy's central engine estimated at 51.3 billion solar masses. It earned its place in the record books partly by swallowing 600 million solar masses of material in one colossal feeding episode.

Host / setting: Central galaxy of a galaxy cluster (radio galaxy)Mass-estimate method: Break radius of the 0.5 kpc galactic coreNotable: Produced a colossal AGN outburst after accreting 600 million solar masses of material
4

TON 618

The famous hyperluminous quasar whose black hole was long cited at 66 billion solar masses — the number NASA used in its 2023 size-comparison animation. A newer analysis revised it down to 40.7 billion, which is the figure used here.

Host / setting: Hyperluminous quasar near the Canes Venatici / Coma Berenices border, ~10.8 billion light-years light-travel distanceMass-estimate method: Quasar C IV emission-line correlation; older H-beta-based estimate was 66 billionNotable: Schwarzschild radius ~1,300 AU, more than 40 times the Sun-Neptune distance
5

SDSS 143148.09+053558

A distant quasar discovered by the Sloan Digital Sky Survey with an estimated 36.4 billion solar masses — the largest SDSS-quasar black hole in the current ranking.

Host / setting: Distant quasar discovered by the Sloan Digital Sky SurveyMass-estimate method: Quasar emission-line correlation; 3.64 x 10^10 M☉Notable: 36.4 billion solar masses, just below TON 618's revised figure
6

SDSS J114833.14+193003.2

Another SDSS quasar black hole at 36.31 billion solar masses — essentially tied with #5, separated by less than 1% of estimated mass.

Host / setting: Distant quasar discovered by the Sloan Digital Sky SurveyMass-estimate method: Mg II / C IV emission-line correlation; 3.631 (+0.550 / -0.625) x 10^10 M☉Notable: Within 1% of #5's mass — effectively a tie given the uncertainties
7

NGC 3842

The brightest galaxy in the Leo Cluster hosts a 34.6 billion-solar-mass black hole — more than triple what earlier estimates suggested for this object.

Host / setting: Brightest galaxy in the Leo ClusterMass-estimate method: Core break radius; 3.46 (+6.30 / -2.24) x 10^10 M☉Notable: Earlier estimates gave at least 9.7 billion solar masses — the current figure is far higher
8

SMSS J215728.21-360215.1

An ultraluminous quasar found by the SkyMapper survey, packing an estimated 34 billion solar masses. It was among the most luminous quasars known when discovered.

Host / setting: Ultraluminous quasar found by the SkyMapper Southern SurveyMass-estimate method: Near-infrared spectroscopy of the Mg II emission-line doublet; 3.4 (+/- 0.6) x 10^10 M☉Notable: Ranked among the most luminous quasars known at discovery
9

SDSS J102325.31+514251.0

A third SDSS quasar on this list, estimated at 33.1 billion solar masses via the magnesium emission-line technique.

Host / setting: Distant quasar discovered by the Sloan Digital Sky SurveyMass-estimate method: Quasar Mg II emission-line correlation; 3.31 (+0.67 / -0.56) x 10^10 M☉Notable: 33.1 billion solar masses — nearly 8,000 times the Milky Way's central black hole
10

Abell 1201 BCG

The brightest galaxy in the Abell 1201 cluster holds a 32.7 billion-solar-mass black hole — one of the rare few weighed by gravitational lensing rather than light from orbiting gas.

Host / setting: Brightest cluster galaxy of Abell 1201Mass-estimate method: Strong gravitational lensing of a background galaxy; 3.27 (+/- 0.71) x 10^10 M☉Notable: One of few supermassive black holes measured via lensing; an earlier estimate was 13 billion

Full comparison

# Name Host / settingMass-estimate methodNotable
1 Phoenix A Brightest galaxy of the Phoenix Cluster (SPT-CLJ2344-4243), about 5.8 billion light-years awayCalorimetric model of adiabatic core regrowth (indirect); not measured directlyCurrent record holder; a 2024 study gave a competing estimate of ~12.6 billion solar masses
2 IC 1101 Center of the Abell 2029 galaxy cluster; host is one of the largest known galaxies, about 1.7 million light-years acrossBreak radius of the central core; 9.77 (+17.14 / -6.22) x 10^10 M☉Uncertainty range spans ~35 to ~270 billion solar masses
3 4C +74.13 Central galaxy of a galaxy cluster (radio galaxy)Break radius of the 0.5 kpc galactic coreProduced a colossal AGN outburst after accreting 600 million solar masses of material
4 TON 618 Hyperluminous quasar near the Canes Venatici / Coma Berenices border, ~10.8 billion light-years light-travel distanceQuasar C IV emission-line correlation; older H-beta-based estimate was 66 billionSchwarzschild radius ~1,300 AU, more than 40 times the Sun-Neptune distance
5 SDSS 143148.09+053558 Distant quasar discovered by the Sloan Digital Sky SurveyQuasar emission-line correlation; 3.64 x 10^10 M☉36.4 billion solar masses, just below TON 618's revised figure
6 SDSS J114833.14+193003.2 Distant quasar discovered by the Sloan Digital Sky SurveyMg II / C IV emission-line correlation; 3.631 (+0.550 / -0.625) x 10^10 M☉Within 1% of #5's mass — effectively a tie given the uncertainties
7 NGC 3842 Brightest galaxy in the Leo ClusterCore break radius; 3.46 (+6.30 / -2.24) x 10^10 M☉Earlier estimates gave at least 9.7 billion solar masses — the current figure is far higher
8 SMSS J215728.21-360215.1 Ultraluminous quasar found by the SkyMapper Southern SurveyNear-infrared spectroscopy of the Mg II emission-line doublet; 3.4 (+/- 0.6) x 10^10 M☉Ranked among the most luminous quasars known at discovery
9 SDSS J102325.31+514251.0 Distant quasar discovered by the Sloan Digital Sky SurveyQuasar Mg II emission-line correlation; 3.31 (+0.67 / -0.56) x 10^10 M☉33.1 billion solar masses — nearly 8,000 times the Milky Way's central black hole
10 Abell 1201 BCG Brightest cluster galaxy of Abell 1201Strong gravitational lensing of a background galaxy; 3.27 (+/- 0.71) x 10^10 M☉One of few supermassive black holes measured via lensing; an earlier estimate was 13 billion

How we ranked this

Ranked by estimated black hole mass in billions of solar masses (M☉), using the primary mass estimate shown for each object in Wikipedia's ordered List of most massive black holes as of 2026-09-21. Where multiple studies give different values, the list's current first-listed (primary) figure is used; competing estimates are noted in the item's facts. Inclusion: the ten highest-mass entries on that list. Mass estimates of supermassive black holes are inherently uncertain and routinely revised — the order reflects current published estimates, not physical certainty.

FAQ

What is the most massive black hole ever discovered?

Phoenix A, at the center of the Phoenix galaxy cluster, is the current record holder with an estimated mass of about 100 billion Suns. But that estimate is indirect — it has never been measured directly — and a 2024 study suggested it could be as low as 12.6 billion, so the record is contested.

How do astronomers weigh black holes they can't see directly?

Four main techniques: tracking the speeds of stars and gas orbiting the black hole, measuring the width of emission lines from hot gas swirling around quasars, modeling the 'break radius' of a galaxy's core, and gravitational lensing. Each carries large uncertainties, which is why published masses often get revised.

Is TON 618 bigger than Phoenix A?

No, per current estimates. TON 618 is now estimated at about 40.7 billion solar masses (an older, widely repeated figure said 66 billion), while Phoenix A is estimated at about 100 billion. Both numbers are model-dependent estimates rather than direct measurements.

How big can a black hole get?

Theory suggests typical actively feeding black holes top out around 50 billion solar masses, with up to about 270 billion possible at maximal spin. Some researchers have proposed 'stupendously large' black holes beyond even 100 billion, but none are confirmed.

Sources

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