List of smallest stars
This is an incomplete list of the smallest known stars. Most of the stars in this list are within the Milky Way except BAT99-123 (near the end of the list), which is in the Large Magellanic Cloud.
Smallest stars are mostly red dwarfs, brown dwarfs, white dwarfs and neutron stars.
1 solar radius (radius of the Sun) = 695700 km
| Star name | Star radius
(in solar radii) |
Star type | Notes |
|---|---|---|---|
| RX J0720.4-3125 | 0.000007187 | Neutron star | |
| 4U 1820-30 | 0.00001308035 | Pulsar | |
| PSR B1257+12 | 0.00001437401 | Pulsar | Coolest neutron star known. Orbited by 3 exoplanets. |
| Crab Pulsar | 0.00001437401 | Pulsar | A very young neutron star (went supernova in 1054 AD) |
| Geminga | 0.00001437401 | Pulsar | |
| PSR B0943+10 | 0.00001437401 | Pulsar | Hottest neutron star known |
| XTE J1739-285 | 0.00001566767 | Neutron star or quark star | |
| Vela Pulsar | 0.00001799626 | Pulsar | |
| PSR J0348+0432 A | 0.00001868621 | Pulsar | |
| PSR J1748-2446ad | 0.00002299841 | Pulsar | Fastest rotating neutron star known |
| PSR B1620-26 A | 0.00003737243 | Pulsar | Orbited by one of the oldest exoplanets known |
| HD 49798 | 0.0023 | White dwarf | One of the hottest white dwarfs known, |
| GRW+70 8247 | 0.0047 | White dwarf | |
| BPM 37093 | 0.0057 | White dwarf | |
| IK Pegasi B | 0.006 | White dwarf | One of the closest stars to Earth that can possibly become a Type Ia supernova. |
| Sirius B | 0.0079 | White dwarf | Closest known white dwarf |
| Earth (for comparison) | 0.00916 | Rocky planet | Reported for reference |
| AR Scorpii | 0.01 | White dwarf | Only known white dwarf pulsar |
| DN Draconis | 0.01 | White dwarf | |
| Van Maanen 2 | 0.011 | White dwarf | |
| Procyon B | 0.0124 | White dwarf | |
| ESO 439-26 | 0.0126 | White dwarf | Least luminous white dwarf known |
| WD 1145+017 | 0.02 | White dwarf | |
| NGC 3132 Central Star | 0.0323 | Proto-white dwarf | Has an A-type star companion. |
| KPD 0005+5106 | 0.055 | White dwarf | One of the hottest white dwarfs known |
| PSR J0348+0432 B | 0.0651 | White dwarf | |
| TMTS J052610.43+593445.1 | 0.0659 | B type subdwarf | Smallest known non-degenerate star. |
| [MCG2003] Sex A PN 1 Central Star | 0.079 | O type subdwarf | |
| CWISE J124909.08+362116.0 | 0.08 | Brown dwarf or red dwarf | A hypervelocity star. |
| Epsilon Indi Ba | 0.08 | Brown dwarf | |
| Epsilon Indi Bb | 0.082 | Brown dwarf | |
| Luhman 16A | 0.085 | Brown dwarf | Nearest brown dwarf system to the Sun. |
| EBLM J0555-57Ab | 0.0862 | Red dwarf | Commonly known as the lower limit for main sequence stars. |
| SSSPM J0829-1309 | 0.088 | Red dwarf | |
| WISE 0855-0714 | 0.09 | Brown dwarf | The coolest star known (temperature very similar to Earth). |
| 2MASS 0939-2448 | 0.09 | Brown dwarf | |
| SCR 1845-6357 B | 0.096 | Brown dwarf | |
| SCR 1845-6357 A | 0.096 | Red dwarf | |
| Jupiter (for comparison) | 0.1 | Gas giant planet | Reported for reference |
| CoRoT-3b | 0.1 | Brown dwarf | |
| HD 114762 B | 0.1 | Red dwarf | |
| R Aquarii B | 0.1 | White dwarf | |
| 2MASS J0523-1403 | 0.101 | Red dwarf | Coolest and least massive main sequence star known |
| LHS 2924 | 0.103 | Red dwarf | |
| Luhman 16B | 0.104 | Brown dwarf | Nearest brown dwarf system to the Sun. |
| 2MASS J04285096-2253227 | 0.1095 | Red dwarf | |
| DX Cancri | 0.11 | Red dwarf | |
| LHS 292 | 0.11 | Red dwarf | |
| TVLM 513-46546 | 0.11 | Red dwarf | |
| Gliese 229B | 0.112 | Brown dwarf | |
| OGLE-TR-122B | 0.116 | Red dwarf | |
| VB 10 | 0.1183 | Red dwarf | |
| TRAPPIST-1 | 0.1192 | Red dwarf | Orbited by at least 7 confirmed Earth-sized rocky exoplanets, at least 3 are potentially habitable. |
| Teegarden's star | 0.12 | Red dwarf | Has 2 potentially habitable exoplanets. |
| LHS 2090 | 0.12 | Red dwarf | |
| VB 8 | 0.1214 | Red dwarf | |
| SPECULOOS-3 | 0.123 | Red dwarf | |
| CFBDSIR 1458+10B | 0.13 | Brown dwarf | |
| Teide 1 | 0.13 | Brown dwarf | |
| Gliese 412B | 0.13 | Red dwarf | |
| Wolf 359 | 0.145 | Red dwarf | |
| NN Serpentis B | 0.15 | Red dwarf | |
| CFBDSIR 1458+10A | 0.15 | Brown dwarf | |
| Proxima Centauri | 0.1542 | Red dwarf | Closest star to Sun. |
| UV Ceti | 0.16 | Red dwarf | |
| BL Ceti | 0.167 | Red dwarf | |
| YZ Ceti | 0.168 | Red dwarf | |
| UY Sextantis | 0.17 | B type subdwarf | A B type subdwarf star is a star with temperatures similar to B type main sequence stars but are significantly smaller and less luminous. |
| Cha 110913-773444 | 0.18 | Brown dwarf | One of the least massive stars known |
| HW Virginis | 0.183 | B type subdwarf | |
| Barnard's star | 0.187 | Red dwarf | |
| Ross 248 | 0.19 | Red dwarf | Will become closest star to Sun about 35000 years later |
| Ross 128 | 0.1967 | Red dwarf | |
| Ross 154 | 0.2 | Red dwarf | |
| Kepler-70 | 0.2 | B type subdwarf | |
| Wolf 227 | 0.2 | Red dwarf | |
| RR Caeli | 0.203 | Red dwarf | |
| Gliese 1214 | 0.204 | Red dwarf | |
| LHS 1140 | 0.2055 | Red dwarf | |
| CT Chamaeleontis B | 0.22 | Brown dwarf | One of the least massive stars known |
| NGC 5882 Central Star | 0.227 | Proto-white dwarf | |
| Fomalhaut C | 0.23 | Red dwarf | |
| OTS 44 | 0.23 | Brown dwarf | One of the least massive stars known |
| CM Draconis B | 0.2396 | Red dwarf | |
| 2M1207A | 0.25 | Brown dwarf | |
| CM Draconis A | 0.2529 | Red dwarf | |
| DG Canum Venaticorum | 0.2529 | Red dwarf | |
| 55 Cancri B | 0.27 | Red dwarf | |
| Kapteyn's star | 0.29 | Red dwarf | |
| Gliese 581 | 0.3 | Red dwarf | |
| Wolf 1061 | 0.319 | Red dwarf | |
| Gliese 1 | 0.33 | Red dwarf | |
| Luyten's star | 0.35 | Red dwarf | |
| Kruger 60A | 0.35 | Red dwarf | |
| Struve 2398A | 0.354 | Red dwarf | |
| Z Andromedae B | 0.36 | White dwarf | Largest and most luminous white dwarf known |
| EV Lacertae | 0.36 | Red dwarf | |
| AT Microscopii B | 0.37 | Red dwarf | |
| Regulus C | 0.37 | Red dwarf | |
| Groombridge 34A | 0.38 | Red dwarf | |
| Lalande 21185 | 0.393 | Red dwarf | |
| AT Microscopii A | 0.41 | Red dwarf | |
| AD Leonis | 0.423 | Red dwarf | |
| Gliese 436 | 0.432 | Red dwarf | |
| WR 93b | 0.44 | Wolf-rayet star | |
| BAT99-123 | 0.47 | Wolf-rayet star | Located in the Large Magellanic Cloud |
| Lacaille 9352 | 0.473 | Red dwarf | |
| Kepler-1 B | 0.5 | Red dwarf | |
| Sun (for comparison) | 1 | G type main sequence star | Reported for reference |