# List of most massive star clusters

Below are lists of the most massive known star clusters in solar masses (M$_☉$) and sorted in descending order.

## Methods for mass estimation
### Globular cluster

Globular cluster masses can be determined by observing the proper motion of nearby stars influenced by the cluster or by estimating the cluster's relaxation time.

### Open clusters

The masses of open star clusters can be estimated by measuring the falloff of radial and tangential velocities of surrounding stars at a particular distance.

## List
### Globular clusters

List of most massive globular clusters :
| Cluster name | Mass (M$_☉$); (Sun = 1×10$^0$) | Galaxy | Notes |
| B037-V327 | 1.08+0.17 −0.049×10$^7$ | Andromeda Galaxy | |
| Mayall II | ≳1×10$^7$ | Andromeda Galaxy | |
| B082-G144 | 6.42+0.16 −0.38×10$^6$ | Andromeda Galaxy | |
| B023-G078 | 6.22+0.03 −0.05×10$^6$ | Andromeda Galaxy | Potentially contains an intermediate-mass black hole of 9.1+2.6 −2.8×10$^4$ M$_☉$. |
| B127-G185 | 5.31+0.28 −0.40×10$^6$ | Andromeda Galaxy | |
| B151-G205 | 4.36+0.16 −0.20×10$^6$ | Andromeda Galaxy | |
| G001-MII | 4.24+0.99 −0.58×10$^6$ | Andromeda Galaxy | |
| B225-G280 | 4.20+0.32 −0.35×10$^6$ | Andromeda Galaxy | |
| ω Centauri | (3.94±0.02)×10$^6$ | Milky Way | Most massive star cluster in the Milky Way. |
| B129 | 3.12+0.11 −0.13×10$^6$ | Andromeda Galaxy | |
| B088-G150 | 2.86+0.33 −0.14×10$^6$ | Andromeda Galaxy | |
| B163-G217 | 2.72+0.11 −0.092×10$^6$ | Andromeda Galaxy | |
| B042-G104 | 2.62+0.30 −0.15×10$^6$ | Andromeda Galaxy | |
| B338-G076 | 2.49+0.28 −0.46×10$^6$ | Andromeda Galaxy | |
| B158-G213 | 2.28+0.25 −0.15×10$^6$ | Andromeda Galaxy | |
| B103-G165 | 2.02+0.13 −0.17×10$^6$ | Andromeda Galaxy | |
| B193-G244 | 1.96+0.086 −0.065×10$^6$ | Andromeda Galaxy | |
| B063-G124 | 1.93+0.27 −0.25×10$^6$ | Andromeda Galaxy | |
| B019-G072 | 1.89+0.26 −0.10×10$^6$ | Andromeda Galaxy | |
| B171-G222 | 1.84+0.16 −0.083×10$^6$ | Andromeda Galaxy | |
| B039-G101 | 1.81+0.23 −0.16×10$^6$ | Andromeda Galaxy | |
| B306-G029 | 1.67+0.21 −0.11×10$^6$ | Andromeda Galaxy | |
| B218-G272 | 1.64+0.27 −0.18×10$^6$ | Andromeda Galaxy | |
| B124-NB10 | 1.60+0.52 −0.55×10$^6$ | Andromeda Galaxy | |
| MITA140 | 1.57+0.14 −0.15×10$^6$ | Andromeda Galaxy | |
| B091D-D058 | 1.54+0.094 −0.11×10$^6$ | Andromeda Galaxy | |
| B020-G073 | 1.51+0.21 −0.16×10$^6$ | Andromeda Galaxy | |
| B116-G178 | 1.45+0.16 −0.073×10$^6$ | Andromeda Galaxy | |
| B182-G233 | 1.41+0.20 −0.24×10$^6$ | Andromeda Galaxy | |
| Messier 54 | (1.41±0.002)×10$^6$ | Milky Way | |
| B094-G156 | 1.38+0.10 −0.11×10$^6$ | Andromeda Galaxy | |
| B174-G226 | 1.36+0.15 −0.19×10$^6$ | Andromeda Galaxy | |
| B147-G199 | 1.34+0.038 −0.041×10$^6$ | Andromeda Galaxy | |
| B055-G116 | 1.32+0.073 −0.085×10$^6$ | Andromeda Galaxy | |
| B006-G058 | 1.31+0.10 −0.049×10$^6$ | Andromeda Galaxy | |
| B178-G229 | 1.28+0.20 −0.21×10$^6$ | Andromeda Galaxy | |
| B206-G257 | 1.27+0.21 −0.29×10$^6$ | Andromeda Galaxy | |
| B068-G130 | 1.26+0.13 −0.10×10$^6$ | Andromeda Galaxy | |
| B311-G033 | 1.24+0.074 −0.14×10$^6$ | Andromeda Galaxy | |
| B034-G096 | 1.23+0.21 −0.092×10$^6$ | Andromeda Galaxy | |
| B012-G064 | 1.23+0.088 −0.14×10$^6$ | Andromeda Galaxy | |
| NGC 6441 | (1.23±0.001)×10$^6$ | Milky Way | |
| B110-G172 | 1.22+0.17 −0.12×10$^6$ | Andromeda Galaxy | |
| B005-G052 | 1.16+0.22 −0.094×10$^6$ | Andromeda Galaxy | |
| B051-G114 | 1.15+0.19 −0.10×10$^6$ | Andromeda Galaxy | |
| B086-G148 | 1.14+0.071 −0.10×10$^6$ | Andromeda Galaxy | |
| B472-D064 | 1.12+0.14 −0.12×10$^6$ | Andromeda Galaxy | |
| B312-G035 | 1.12+0.18 −0.18×10$^6$ | Andromeda Galaxy | |
| B017-G070 | 1.11+0.14 −0.12×10$^6$ | Andromeda Galaxy | |
| B240-G302 | 1.11+0.17 −0.15×10$^6$ | Andromeda Galaxy | |
| B072 | 1.08+0.13 −0.083×10$^6$ | Andromeda Galaxy | |
| B112-G174 | 1.08+0.078 −0.057×10$^6$ | Andromeda Galaxy | |
| B405-G351 | 1.08+0.20 −0.18×10$^6$ | Andromeda Galaxy | |
| B373-G305 | 1.07+0.22 −0.10×10$^6$ | Andromeda Galaxy | |
| B058-G119 | 1.06+0.13 −0.17×10$^6$ | Andromeda Galaxy | |
| NGC 6388 | (1.06±0.001)×10$^6$ | Milky Way | |
| B224-G279 | 1.05+0.11 −0.085×10$^6$ | Andromeda Galaxy | |
| B096-G158 | 1.04+0.067 −0.061×10$^6$ | Andromeda Galaxy | |
| B185-G235 | 1.03+0.11 −0.070×10$^6$ | Andromeda Galaxy | |
| NGC 2419 | (9.81±1.42)×10$^5$ | None | |
| B179-G230 | 9.78+1.33 −1.43×10$^5$ | Andromeda Galaxy | |
| NGC 2808 | 9.73+0.04 −0.04×10$^6$ | Milky Way | |
| Messier 3 | 9.57×10$^5$ | Milky Way | |
| B143-G198 | 9.55+0.31 −0.36×10$^5$ | Andromeda Galaxy | |
| B027-G087 | 9.54+1.35 −1.08×10$^5$ | Andromeda Galaxy | |
| MGC1 | 9.54+1.35 −1.08×10$^5$ | None | |
| EXT8 | 9.40+0.34 −0.31×10$^5$ | Andromeda Galaxy | |
| B204-G254 | 9.22+0.48 −0.71×10$^5$ | Andromeda Galaxy | |
| B205-G256 | 9.16+1.74 −1.57×10$^5$ | Andromeda Galaxy | |
| B045-G108 | 9.06+1.29 −0.60×10$^5$ | Andromeda Galaxy | |
| B135-G192 | 9.04+0.93 −0.80×10$^5$ | Andromeda Galaxy | |
| B061-G122 | 8.98+1.26 −0.75×10$^5$ | Andromeda Galaxy | |
| B131-G189 | 8.85+2.93 −1.32×10$^5$ | Andromeda Galaxy | |
| B383-G318 | 8.80+1.13 −0.90×10$^5$ | Andromeda Galaxy | |
| B381-G315 | 8.69+1.34 −0.66×10$^5$ | Andromeda Galaxy | |
| B212-G263 | 8.62+0.81 −0.68×10$^5$ | Andromeda Galaxy | |
| B107-G169 | 8.59+1.04 −1.32×10$^5$ | Andromeda Galaxy | |
| Messier 5 | 8.57×10$^5$ | Milky Way | |
| B183-G234 | 8.24+0.88 −0.82×10$^5$ | Andromeda Galaxy | |
| B384-G319 | 8.21+0.41 −0.60×10$^5$ | Andromeda Galaxy | |
| NGC 6440 | 8.11×10$^5$ | Milky Way | |
| B232-G286 | 8.01+0.91 −0.39×10$^5$ | Andromeda Galaxy | |
| B122-G181 | 7.88+1.34 −0.72×10$^5$ | Andromeda Galaxy | |
| B073-G134 | 7.80+0.53 −0.64×10$^5$ | Andromeda Galaxy | |
| NGC 5824 | (7.79±0.42)×10$^5$ | Milky Way | |
| Messier 13 | 7.75×10$^5$ | Milky Way | |
| B386-G322 | 7.74+2.31 −1.69×10$^5$ | Andromeda Galaxy | |
| Messier 14 | (7.74±0.61)×10$^5$ | Milky Way | |
| B106-G168 | 7.54+0.54 −0.52×10$^5$ | Andromeda Galaxy | |
| B313-G036 | 7.41+1.34 −1.01×10$^5$ | Andromeda Galaxy | |
| NGC 5286 | 7.13×10$^5$ | Milky Way | |
| B030-G091 | 7.10+0.32 −0.39×10$^5$ | Andromeda Galaxy | |
| ξ Tucanae (47 Tucanae) | 7.10×10$^5$ | Milky Way | |
| Messier 62 | (7.07±0.05)×10$^5$ | Milky Way | |
| PA53 | 6.93+1.47 −0.81×10$^5$ | Andromeda Galaxy | |
| B153 | 6.86+5.45 −0.79×10$^5$ | Andromeda Galaxy | |
| Messier 19 | (6.80±0.59)×10$^5$ | Milky Way | |
| Liller 1 | (6.66±1.17)×10$^5$ | Milky Way | |
| B109-G170 | 6.63+0.71 −0.62×10$^5$ | Andromeda Galaxy | |
| B514-MCGC4 | 6.52+0.76 −0.58×10$^5$ | Andromeda Galaxy | |
| B080-G141 | 6.50+1.00 −0.74×10$^5$ | Andromeda Galaxy | |
| B148-G200 | 6.49+1.14 −0.96×10$^5$ | Andromeda Galaxy | |
| Messier 22 | 6.44×10$^5$ | Milky Way | |
| B370-G300 | 6.40+0.56 −0.81×10$^5$ | Andromeda Galaxy | |
| PA16 | 6.27+0.32 −0.29×10$^5$ | Andromeda Galaxy | |
| Messier 2 | 6.27+0.09 −0.09×10$^5$ | Milky Way | |
| B379-G312 | 6.25+0.69 −0.47×10$^5$ | Andromeda Galaxy | |
| Messier 15 | 6.14+0.07 −0.07×10$^5$ | Milky Way | |
| NGC 5986 | 5.99×10$^5$ | Milky Way | |
| B038-G098 | 5.98+0.72 −0.30×10$^5$ | Andromeda Galaxy | |
| B078-G140 | 5.94+0.93 −0.50×10$^5$ | Andromeda Galaxy | |
| B044-G107 | 5.93+0.86 −0.61×10$^5$ | Andromeda Galaxy | |
| B029-G090 | 5.92+1.57 −0.66×10$^5$ | Andromeda Galaxy | |
| G002-MIII | 5.90+0.47 −0.30×10$^5$ | Andromeda Galaxy | |
| Messier 75 | (5.86±1.24)×10$^5$ | Milky Way | |
| B180-G231 | 5.83+1.01 −0.68×10$^5$ | Andromeda Galaxy | |
| B260 | 5.76+1.37 −0.63×10$^5$ | Andromeda Galaxy | |
| B344-G127 | 5.74+0.76 −0.87×10$^5$ | Andromeda Galaxy | |
| NGC 6541 | 5.72×10$^5$ | Milky Way | |
| Terzan 5 | (5.66±0.71)×10$^5$ | Milky Way | |
| NGC 6139 | 5.66×10$^5$ | Milky Way | |
| B233-G287 | 5.51+0.79 −1.23×10$^5$ | Andromeda Galaxy | |
| NGC 6284 | (5.51±1.13)×10$^5$ | Milky Way | |
| NGC 1851 | 5.51×10$^5$ | Milky Way | |
| Messier 28 | 5.51×10$^5$ | Milky Way | |
| B403-G348 | 5.45+0.82 −0.45×10$^5$ | Andromeda Galaxy | |
| B098 | 5.38+0.25 −0.30×10$^5$ | Andromeda Galaxy | |
| NGC 6539 | 5.36×10$^5$ | Milky Way | |
| NGC 6539 | 5.36×10$^5$ | Milky Way | |
| B257-V219 | 5.35+1.17 −0.58×10$^5$ | Andromeda Galaxy | |
| B001-G039 | 5.34+0.85 −0.48×10$^5$ | Andromeda Galaxy | |
| Messier 53 | 5.3+0.1 −0.1×10$^5$ | Milky Way | |
| NGC 6517 | 5.26×10$^5$ | Milky Way | |
| B001-G039 | 5.04+0.39 −0.35×10$^5$ | Andromeda Galaxy | |
| PA46 | 5.02+0.53 −0.36×10$^5$ | Andromeda Galaxy | |
| Messier 80 | 5.02×10$^5$ | Milky Way | |
| B130-G188 | 5.01+0.42 −0.56×10$^5$ | Andromeda Galaxy | |

### Open clusters

List of most massive open clusters :
| Cluster name | Mass (M$_☉$); (Sun = 1) | Galaxy | Notes |
| NGC 1569-B | (4.4±1.1)×10$^5$ | NGC 1569 | |
| NGC 1569-A | (3.3±0.5)×10$^5$ | NGC 1569 | |
| RMC 136 | 8.7×10$^4$ | Large Magellanic Cloud | Contains the most massive known star R136a1 at 196+34 −27 M$_☉$. |
| NGC 346 | 5×10$^4$ | Small Magellanic Cloud | |
| Ara Cluster (Westerlund 1) | 4.4 – 5.7 × 10$^4$ | Milky Way | |
| Stephenson 2 (RSGC2) | 4×10$^4$ | Milky Way | |
| RSGC1 | (3±1)×10$^4$ | Milky Way | |
| RSGC3 | (3±1)×10$^4$ | Milky Way | |
| NGC 3603 | (1.9±0.6)×10$^4$ | Milky Way | |