List of smallest stars

This is a list of stars which are the least voluminous known (the smallest stars by volume).

List

This list is incomplete; you can help by expanding it.

Notable small stars

This is a list of small stars that are otherwise notable for characteristics that are not separately listed.

Star name	Star mean radius, kilometres	Star class	Notes	References
PSR B0943+10	2.6	Pulsar (quark star?)	Neutron stars are stellar remnants produced by stars with around 8-9 solar masses or more explodes in a supernova at the end of its life. They are usually produced by stars with less than 20 solar masses, although a more massive star may produce a neutron star in certain cases. PSR B0943+10 is one of the least massive stars with 0.02 solar masses.	[1]
PSR B1257+12	10	Pulsar	Orbited by three planets.	[2]
PSR B0531+21 (Crab pulsar)	10			[3]
Geminga	10			[4]
Vela pulsar	10			[5]
XTE J1739-285	10.9	Pulsar (quark star?)		[6]
PSR J0348+0432 A	13 + 2		Orbited by a white dwarf star (see below)	[7]
PSR J1748-2446ad	<16	Pulsar	Fastest-spinning pulsar known.	[8]
XTE J1650-500 B	24	black hole	This binary X-ray transient system, XTE J1650-500, component black hole, at 3.8 solar masses, is smaller than the previous recordholder GRO J1655-40 B of 6.3 MSun in the microquasar system GRO J1655-40.	[9]
GRW +70 8247	3300	white dwarf	Smallest white dwarf star known	[10]
Sirius B	5466		Historically first detected white dwarf star	[11]
LB 1497	5494.5			[12]
40 Eridani B	5547.5
ZZ Ceti	5890
GD 165	5998
G 29-38	6000
Procyon B	6700			[13][14]
ESO 439-26	8775.5		Faintest known white dwarf.[15]
Van Maanen 2	9048			[16]
PSR J0348+0432 B	45268		A white dwarf that orbits its pulsar companion (see above)	[7]
WD 1145+017	13926.84		Host star of one of the smallest exoplanets.	[17]
EBLM J0555-57Ab	59000	red dwarf	This red dwarf is slightly larger than the planet Saturn. As of 2019, it is the second lightest hydrogen-fusing star known, marginally heavier (0.0777-0.0852M☉) than the 2MASS J0523-1403. Although its mass is comparable to that of TRAPPIST-1A, its radius is 1/3 smaller.	[18][19][20]
SSSPM J0829-1309	61300			[21]
2MASS J0523-1403	70600		As in 2019, with mass 67.54±12.79MJ (0.0523-0.0767M☉) is the lowest known mass hydrogen-burning star.	[22][21][23]
OGLE-TR-122B	81100		This was once the smallest known actively fusing star, when found in 2005, through 2013. It is the smallest eclipsing red dwarf, and smallest observationally measured diameter.	[24][25][26]
Gliese 229 B	83480	brown dwarf		[27]
TRAPPIST-1	84180	red dwarf	Hosts a planetary system with at least seven rocky planets.	[28]
Teegarden's Star	88354		Two potentially habitable planets	[29]
Luyten 726-8 (A and B)	97000			[30]
Proxima Centauri	101000		This is the nearest neighbouring star to the Sun.	[31]
Wolf 359	111400			[32]
Ross 248	111400			[33]
Barnard's Star	136400			[34]
CM Draconis B	167000			[35]
Ross 154	167000			[36]
CM Draconis A	176000			[35]
Z Andromedae B	184530.63[37]	White dwarf	Largest white dwarf	[37]
Kapteyn's Star	203000	Red dwarf	This is the closest halo star to the Sun.	[31]
Luyten's Star	243500			[38]
Teide 1	270240	Brown dwarf		[39]
Lalande 21185	273500	Red dwarf		[40]
Lacaille 9352	320000			[41]

Smallest stars by type

List of the smallest stars by star type

Type	Star name	Radius Solar radii (Sun = 1)	Radius Jupiter radii (Jupiter = 1)	Radius Earth radii (Earth = 1)	Radius (km / mi)	Date	Notes	References
Red dwarf	EBLM J0555-57Ab	0.084	0.84		59,000 km (37,000 mi)	2017	The red dwarf stars are considered the smallest stars known, and representative of the smallest star possible.	[18][19][20]
Brown dwarf	Cha 110913-773444					2004	Brown dwarfs are not massive enough to build up the pressure in the central regions to allow nuclear fusion of hydrogen into helium. They are best described as extremely massive gas giants that were not able to ignite into a hydrogen-fusing star.	[42]
White dwarf	GRW +70 8247	0.0047	0.047	0.52	3,300 km (2,100 mi)	1934	White dwarfs are stellar remnants produced when a star with around 8 solar masses or less sheds its outer layers into a planetary nebula. The leftover core becomes the white dwarf. It is thought that white dwarfs cool down over quadrillions of years to produce a black dwarf.	[10]
Neutron star	PSR B0943+10				2.6 km (1.61 mi)		Neutron stars are stellar remnants produced by stars with around 9 solar masses or more explodes in a supernova at the end of its life. They are usually produced by stars with less than 20 solar masses, although a more massive star may produce a neutron star in certain cases. PSR B0943+10 is one of the least massive stars with 0.02 solar masses.
Stellar-mass black hole	XTE J1650-500 B				24 km (15 mi)	2008	Black holes are stellar remnants usually produced when extremely massive stars explode in a supernova or hypernova at the end of their lives.	[9]

Timeline of smallest red dwarf star recordholders

Red dwarfs are considered the smallest star known that are active fusion stars, and are the smallest stars possible that is not a brown dwarf.

List of smallest red dwarf titleholders

Star name	Date	Radius Solar radii (Sun = 1)	Radius Jupiter radii (Jupiter = 1)	Radius km (mi)	Notes
EBLM J0555-57Ab	2017—	0.085	0.85	59,000 km (37,000 mi)	This star is slightly larger than the planet Saturn.	[18][19][20]
2MASS J0523-1403	2013-2017	0.102	1.01	70,600 km (43,900 mi)	Lowest mass main sequence star as in 2020.	[22][21][43][44]
OGLE-TR-122B	2005-2013	0.117	1.16	81,100 km (50,400 mi)		[24][25][26]

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