There are 37 known isotopes of radon (₈₆Rn), from ¹⁹⁵Rn to ²³¹Rn; all are radioactive. The most stable isotope is ²²²Rn with a half-life of 3.823 days, which decays into . Five isotopes of radon, ^{217, 218, 219, 220, 222}Rn occur in trace quantities in nature as

decay product In nuclear physics, a decay product (also known as a daughter product, daughter isotope, radio-daughter, or daughter nuclide) is the remaining nuclide left over from radioactive decay. Radioactive decay often proceeds via a sequence of steps ( ...

s of, respectively, ²¹⁷At, ²¹⁸At, ²²³Ra, ²²⁴Ra, and ²²⁶Ra. ²¹⁷Rn is produced in a rare branch in the decay chain of trace quantities of ²³⁷Np; ²¹⁸Rn and ²²²Rn are intermediate steps in the decay chain for ²³⁸U; ²¹⁹Rn is an intermediate step in the decay chain for ²³⁵U; and ²²⁰Rn occurs in the decay chain for ²³²Th.

List of isotopes

, - , ¹⁹⁵Rn , , style="text-align:right" , 86 , style="text-align:right" , 109 , 195.00544(5) , 6 ms , , , 3/2−# , , - , style="text-indent:1em" , ^195mRn , , colspan="3" style="text-indent:2em" , 50(50) keV , 6 ms , , , 13/2+# , , - , rowspan=2, ¹⁹⁶Rn , rowspan=2, , rowspan=2 style="text-align:right" , 86 , rowspan=2 style="text-align:right" , 110 , rowspan=2, 196.002115(16) , rowspan=2, 4.7(11) ms
.4(+13−9) ms, α , ¹⁹²Po , rowspan=2, 0+ , rowspan=2, , - , β⁺ (rare) , ¹⁹⁶At , - , rowspan=2, ¹⁹⁷Rn , rowspan=2, , rowspan=2 style="text-align:right" , 86 , rowspan=2 style="text-align:right" , 111 , rowspan=2, 197.00158(7) , rowspan=2, 66(16) ms
5(+23−14) ms, α , ¹⁹³Po , rowspan=2, 3/2−# , rowspan=2, , - , β⁺ (rare) , ¹⁹⁷At , - , rowspan=2 style="text-indent:1em" , ^197mRn , rowspan=2, , rowspan=2 colspan="3" style="text-indent:2em" , 200(60)# keV , rowspan=2, 21(5) ms
9(+8−4) ms, α , ¹⁹³Po , rowspan=2, (13/2+) , rowspan=2, , - , β⁺ (rare) , ¹⁹⁷At , - , rowspan=2, ¹⁹⁸Rn , rowspan=2, , rowspan=2 style="text-align:right" , 86 , rowspan=2 style="text-align:right" , 112 , rowspan=2, 197.998679(14) , rowspan=2, 65(3) ms , α (99%) , ¹⁹⁴Po , rowspan=2, 0+ , rowspan=2, , - , β⁺ (1%) , ¹⁹⁸At , - , rowspan=2, ¹⁹⁹Rn , rowspan=2, , rowspan=2 style="text-align:right" , 86 , rowspan=2 style="text-align:right" , 113 , rowspan=2, 198.99837(7) , rowspan=2, 620(30) ms , α (94%) , ¹⁹⁵Po , rowspan=2, 3/2−# , rowspan=2, , - , β⁺ (6%) , ¹⁹⁹At , - , rowspan=2 style="text-indent:1em" , ^199mRn , rowspan=2, , rowspan=2 colspan="3" style="text-indent:2em" , 180(70) keV , rowspan=2, 320(20) ms , α (97%) , ¹⁹⁵Po , rowspan=2, 13/2+# , rowspan=2, , - , β⁺ (3%) , ¹⁹⁹At , - , rowspan=2, ²⁰⁰Rn , rowspan=2, , rowspan=2 style="text-align:right" , 86 , rowspan=2 style="text-align:right" , 114 , rowspan=2, 199.995699(14) , rowspan=2, 0.96(3) s , α (98%) , ¹⁹⁶Po , rowspan=2, 0+ , rowspan=2, , - , β⁺ (2%) , ²⁰⁰At , - , rowspan=2, ²⁰¹Rn , rowspan=2, , rowspan=2 style="text-align:right" , 86 , rowspan=2 style="text-align:right" , 115 , rowspan=2, 200.99563(8) , rowspan=2, 7.0(4) s , α (80%) , ¹⁹⁷Po , rowspan=2, (3/2−) , rowspan=2, , - , β⁺ (20%) , ²⁰¹At , - , rowspan=3 style="text-indent:1em" , ^201mRn , rowspan=3, , rowspan=3 colspan="3" style="text-indent:2em" , 280(90)# keV , rowspan=3, 3.8(1) s , α (90%) , ¹⁹⁷Po , rowspan=3, (13/2+) , rowspan=3, , - , β⁺ (10%) , ²⁰¹At , - , IT (<1%) , ²⁰¹Rn , - , rowspan=2, ²⁰²Rn , rowspan=2, , rowspan=2 style="text-align:right" , 86 , rowspan=2 style="text-align:right" , 116 , rowspan=2, 201.993263(19) , rowspan=2, 9.94(18) s , α (85%) , ¹⁹⁸Po , rowspan=2, 0+ , rowspan=2, , - , β⁺ (15%) , ²⁰²At , - , rowspan=2, ²⁰³Rn , rowspan=2, , rowspan=2 style="text-align:right" , 86 , rowspan=2 style="text-align:right" , 117 , rowspan=2, 202.993387(25) , rowspan=2, 44.2(16) s , α (66%) , ¹⁹⁹Po , rowspan=2, (3/2−) , rowspan=2, , - , β⁺ (34%) , ²⁰³At , - , rowspan=2 style="text-indent:1em" , ^203mRn , rowspan=2, , rowspan=2 colspan="3" style="text-indent:2em" , 363(4) keV , rowspan=2, 26.7(5) s , α (80%) , ¹⁹⁹Po , rowspan=2, 13/2(+) , rowspan=2, , - , β⁺ (20%) , ²⁰³At , - , rowspan=2, ²⁰⁴Rn , rowspan=2, , rowspan=2 style="text-align:right" , 86 , rowspan=2 style="text-align:right" , 118 , rowspan=2, 203.991429(16) , rowspan=2, 1.17(18) min , α (73%) , ²⁰⁰Po , rowspan=2, 0+ , rowspan=2, , - , β⁺ (27%) , ²⁰⁴At , - , rowspan=2, ²⁰⁵Rn , rowspan=2, , rowspan=2 style="text-align:right" , 86 , rowspan=2 style="text-align:right" , 119 , rowspan=2, 204.99172(5) , rowspan=2, 170(4) s , β⁺ (77%) , ²⁰⁵At , rowspan=2, 5/2− , rowspan=2, , - , α (23%) , ²⁰¹Po , - , rowspan=2, ²⁰⁶Rn , rowspan=2, , rowspan=2 style="text-align:right" , 86 , rowspan=2 style="text-align:right" , 120 , rowspan=2, 205.990214(16) , rowspan=2, 5.67(17) min , α (62%) , ²⁰²Po , rowspan=2, 0+ , rowspan=2, , - , β⁺ (38%) , ²⁰⁶At , - , rowspan=2, ²⁰⁷Rn , rowspan=2, , rowspan=2 style="text-align:right" , 86 , rowspan=2 style="text-align:right" , 121 , rowspan=2, 206.990734(28) , rowspan=2, 9.25(17) min , β⁺ (79%) , ²⁰⁷At , rowspan=2, 5/2− , rowspan=2, , - , α (21%) , ²⁰³Po , - , style="text-indent:1em" , ^207mRn , , colspan="3" style="text-indent:2em" , 899.0(10) keV , 181(18) µs , , , (13/2+) , , - , rowspan=2, ²⁰⁸Rn , rowspan=2, , rowspan=2 style="text-align:right" , 86 , rowspan=2 style="text-align:right" , 122 , rowspan=2, 207.989642(12) , rowspan=2, 24.35(14) min , α (62%) , ²⁰⁴Po , rowspan=2, 0+ , rowspan=2, , - , β⁺ (38%) , ²⁰⁸At , - , rowspan=2, ²⁰⁹Rn , rowspan=2, , rowspan=2 style="text-align:right" , 86 , rowspan=2 style="text-align:right" , 123 , rowspan=2, 208.990415(21) , rowspan=2, 28.5(10) min , β⁺ (83%) , ²⁰⁹At , rowspan=2, 5/2− , rowspan=2, , - , α (17%) , ²⁰⁵Po , - , style="text-indent:1em" , ^209m1Rn , , colspan="3" style="text-indent:2em" , 1173.98(13) keV , 13.4(13) µs , , , 13/2+ , , - , style="text-indent:1em" , ^209m2Rn , , colspan="3" style="text-indent:2em" , 3636.78(23) keV , 3.0(3) µs , , , (35/2+) , , - , rowspan=2, ²¹⁰Rn , rowspan=2, , rowspan=2 style="text-align:right" , 86 , rowspan=2 style="text-align:right" , 124 , rowspan=2, 209.989696(9) , rowspan=2, 2.4(1) h , α (96%) , ²⁰⁶Po , rowspan=2, 0+ , rowspan=2, , - , β⁺ (4%) , ²¹⁰At , - , style="text-indent:1em" , ^210m1Rn , , colspan="3" style="text-indent:2em" , 1690(15) keV , 644(40) ns , , , 8+# , , - , style="text-indent:1em" , ^210m2Rn , , colspan="3" style="text-indent:2em" , 3837(15) keV , 1.06(5) µs , , , (17)− , , - , style="text-indent:1em" , ^210m3Rn , , colspan="3" style="text-indent:2em" , 6493(15) keV , 1.04(7) µs , , , (22)+ , , - , rowspan=2, ²¹¹Rn , rowspan=2, , rowspan=2 style="text-align:right" , 86 , rowspan=2 style="text-align:right" , 125 , rowspan=2, 210.990601(7) , rowspan=2, 14.6(2) h , α (72.6%) , ²⁰⁷Po , rowspan=2, 1/2− , rowspan=2, , - , β⁺ (27.4%) , ²¹¹At , - , rowspan=2, ²¹²Rn , rowspan=2, , rowspan=2 style="text-align:right" , 86 , rowspan=2 style="text-align:right" , 126 , rowspan=2, 211.990704(3) , rowspan=2, 23.9(12) min , α , ²⁰⁸Po , rowspan=2, 0+ , rowspan=2, , - , β⁺β⁺ (rare) , ²¹²Po , - , ²¹³Rn , , style="text-align:right" , 86 , style="text-align:right" , 127 , 212.993883(6) , 19.5(1) ms , α , ²⁰⁹Po , (9/2+) , , - , rowspan=2, ²¹⁴Rn , rowspan=2, , rowspan=2 style="text-align:right" , 86 , rowspan=2 style="text-align:right" , 128 , rowspan=2, 213.995363(10) , rowspan=2, 0.27(2) µs , α , ²¹⁰Po , rowspan=2, 0+ , rowspan=2, , - , β⁺β⁺ (rare) , ²¹⁴Po , - , style="text-indent:1em" , ^214mRn , , colspan="3" style="text-indent:2em" , 4595.4 keV , 245(30) ns , , , (22+) , , - , ²¹⁵Rn , , style="text-align:right" , 86 , style="text-align:right" , 129 , 214.998745(8) , 2.30(10) µs , α , ²¹¹Po , 9/2+ , , - , ²¹⁶Rn , , style="text-align:right" , 86 , style="text-align:right" , 130 , 216.000274(8) , 45(5) µs , α , ²¹²Po , 0+ , , - , ²¹⁷Rn , , style="text-align:right" , 86 , style="text-align:right" , 131 , 217.003928(5) , 0.54(5) ms , α , ²¹³Po , 9/2+ , TraceIntermediate decay product of ²³⁷Np , - , ²¹⁸Rn , , style="text-align:right" , 86 , style="text-align:right" , 132 , 218.0056013(25) , 35(5) ms , α , ²¹⁴Po , 0+ , TraceIntermediate

of ²³⁸U , - , ²¹⁹Rn , Actinon
Actinium emanation , style="text-align:right" , 86 , style="text-align:right" , 133 , 219.0094802(27) , 3.96(1) s , α , ²¹⁵Po , 5/2+ , TraceIntermediate decay product of ²³⁵U , - , rowspan=2, ²²⁰Rn , rowspan=2, Thoron
Thorium emanation , rowspan=2 style="text-align:right" , 86 , rowspan=2 style="text-align:right" , 134 , rowspan=2, 220.0113940(24) , rowspan=2, 55.6(1) s , αTheorized to also undergo β⁻β⁻ dacay to ²²⁰Ra , ²¹⁶Po , rowspan=2, 0+ , rowspan=2, TraceIntermediate decay product of ²³²Th , - , β⁻β⁻ (rare)Predicted, but never observed , ²²⁰Ra , - , rowspan=2, ²²¹Rn , rowspan=2, , rowspan=2 style="text-align:right" , 86 , rowspan=2 style="text-align:right" , 135 , rowspan=2, 221.015537(6) , rowspan=2, 25.7(5) min , β⁻ (78%) , ²²¹Fr , rowspan=2, 7/2(+) , rowspan=2, , - , α (22%) , ²¹⁷Po , - , ²²²Rn , RadonSource of element's name
Radium emanation
Emanation
Emanon
Niton , style="text-align:right" , 86 , style="text-align:right" , 136 , 222.0175777(25) , 3.8235(3) d , αTheorized to also undergo β⁻β⁻ dacay to ²²²Ra , ²¹⁸Po , 0+ , Trace , - , ²²³Rn , , style="text-align:right" , 86 , style="text-align:right" , 137 , 223.02179(32)# , 24.3(4) min , β⁻ , ²²³Fr , 7/2 , , - , ²²⁴Rn , , style="text-align:right" , 86 , style="text-align:right" , 138 , 224.02409(32)# , 107(3) min , β⁻ , ²²⁴Fr , 0+ , , - , ²²⁵Rn , , style="text-align:right" , 86 , style="text-align:right" , 139 , 225.02844(32)# , 4.66(4) min , β⁻ , ²²⁵Fr , 7/2− , , - , ²²⁶Rn , , style="text-align:right" , 86 , style="text-align:right" , 140 , 226.03089(43)# , 7.4(1) min , β⁻ , ²²⁶Fr , 0+ , , - , ²²⁷Rn , , style="text-align:right" , 86 , style="text-align:right" , 141 , 227.03541(45)# , 20.8(7) s , β⁻ , ²²⁷Fr , 5/2(+#) , , - , ²²⁸Rn , , style="text-align:right" , 86 , style="text-align:right" , 142 , 228.03799(44)# , 65(2) s , β⁻ , ²²⁸Fr , 0+ , , - , ²²⁹Rn , , style="text-align:right" , 86 , style="text-align:right" , 143 , 229.0426536(141) , 12(1) s , β⁻ , ²²⁹Fr , , , - , ²³⁰Rn , , style="text-align:right" , 86 , style="text-align:right" , 144 , , , β⁻ , ²³⁰Fr , 0+ , , - , ²³¹Rn
, , style="text-align:right" , 86 , style="text-align:right" , 145 , , , β⁻ , ²³¹Fr , ,

References

* Isotope masses from: ** * Isotopic compositions and standard atomic masses from: ** ** * Half-life, spin, and isomer data selected from the following sources. ** ** ** {{Authority control Isotopes of radon, Radon Radon