Индиумот (49In) се состои од два првобитни нуклиди, при што најчестиот (~ 95,7%) нуклид (115In) е мерлив, но слабо радиоактивен. Неговото распаѓање има полураспад од 4,41×1014 години, многу подолго од моментално прифатената возраст на Вселената.
Стабилниот изотоп 113In е само 4,3% од природниот индиум. Меѓу елементите со познат стабилен изотоп, само телурот и рениумот на сличен начин се појавуваат со стабилен изотоп во помала застапеност од долговечниот радиоактивен изотоп. Освен 115 In, најдолготрајниот радиоизотоп е 111In, со полураспад од 2,8047 дена. Сите други радиоизотопи имаат полураспад помал од еден ден. Овој елемент има и 47 изомери, од кои најдолготрајниот е 114m1In, со полураспад од 49,51 дена. Сите други мета-состојби имаат полураспад помалку од еден ден, повеќето помалку од еден час, а многумина се мерат во милисекунди или помалку.
Индиум-111 се употребува медицински во јадрената слика, како ознака за нуклиди со радиотрасер за локализација на протеински радиофармацевтски препарати со гама камера, како што е октреотид означен со In-111, кој се врзува за рецепторите на одредени ендокрини тумори (Октреоскан). Индиум-111 исто така се користи во скенирањата на белите крвни зрнца на индиум, кои користат јадрени медицински техники за пребарување на скриени инфекции.
Неколку изотопи на индиум богати со протони (вклучувајќи индиум-99) се употребуваат за мерење на масата на двојно-волшебниот изотоп калај-100.
Список на изотопи
|-id=Indium-96 | rowspan=2|96In | rowspan=2 style="text-align:right" | 49 | rowspan=2 style="text-align:right" | 47 | rowspan=2|95.95911(54)# | rowspan=2|1# ms[>400 ns] | β+? | 96Cd | rowspan=2|9/2+# | rowspan=2| | rowspan=2| |- | p? | 95Cd |-id=Indium-97 | rowspan=3|97In | rowspan=3 style="text-align:right" | 49 | rowspan=3 style="text-align:right" | 48 | rowspan=3|96.94913(43)# | rowspan=3|36(6) ms | β+ (97.7%) | 97Cd | rowspan=3|9/2+# | rowspan=3| | rowspan=3| |- | β+, p (2.3%) | 96Ag |- | p? | 96Cd |-id=Indium-97m | style="text-indent:1em" | 97mIn | colspan="3" style="text-indent:2em" | 400(100)# keV | 0.12(7) ms | p? | 96Cd | 1/2−#
|-id=Indium-98 | rowspan=2|98In | rowspan=2 style="text-align:right" | 49 | rowspan=2 style="text-align:right" | 49 | rowspan=2|97.94213(33)# | rowspan=2|30(1) ms | β+ (>99.87%) | 98Cd | rowspan=2|(0+) | rowspan=2| | rowspan=2| |- | β+, p (<0.13%) | 97Ag |-id=Indium-98m | rowspan=2 style="text-indent:1em" | 98mInРедоследот на основната состојба и изомерот е непознат. | rowspan=2 colspan="3" style="text-indent:2em" | 820(730) keV | rowspan=2|890(20) ms | β+ (56%) | 98Cd | rowspan=2|(9+) | rowspan=2| | rowspan=2| |- | β+, p (44%) | 97Ag |-id=Indium-99 | rowspan=2|99In | rowspan=2 style="text-align:right" | 49 | rowspan=2 style="text-align:right" | 50 | rowspan=2|98.93411(32)# | rowspan=2|3.11(6) s | β+ (99.71%) | 99Cd | rowspan=2|9/2+# | rowspan=2| | rowspan=2| |- | β+, p (0.29%) | 98Ag |-id=Indium-100 | rowspan=2|100In | rowspan=2 style="text-align:right" | 49 | rowspan=2 style="text-align:right" | 51 | rowspan=2|99.9311019(24) | rowspan=2|5.62(6) s | β+ (98.34%) | 100Cd | rowspan=2|6+# | rowspan=2| | rowspan=2| |- | β+, p (1.66%) | 99Ag |-id=Indium-101 | rowspan=2|101In | rowspan=2 style="text-align:right" | 49 | rowspan=2 style="text-align:right" | 52 | rowspan=2|100.926414(13) | rowspan=2|15.1(11) s | β+ (>98.3%) | 101Cd | rowspan=2|(9/2+) | rowspan=2| | rowspan=2| |- | β+, p (<1.7%) | 100Ag |-id=Indium-101m | rowspan=2 style="text-indent:1em" | 101mIn | rowspan=2 colspan="3" style="text-indent:2em" | 640(40) keV | rowspan=2|10# s | β+? | 101Cd | rowspan=2|1/2−# | rowspan=2| | rowspan=2| |- | ИП? | 101In |-id=Indium-102 | rowspan=2|102In | rowspan=2 style="text-align:right" | 49 | rowspan=2 style="text-align:right" | 53 | rowspan=2|101.9241059(49) | rowspan=2|23.3(1) s | β+ (99.99%) | 102Cd | rowspan=2|(6+) | rowspan=2| | rowspan=2| |- | β+, p (0.0093%) | 101Ag |-id=Indium-103 | 103In | style="text-align:right" | 49 | style="text-align:right" | 54 | 102.9198788(96) | 60(1) s | β+ | 103Cd | (9/2+)
|-id=Indium-103m | rowspan=2 style="text-indent:1em" | 103mIn | rowspan=2 colspan="3" style="text-indent:2em" | 631.7(1) keV | rowspan=2|34(2) s | β+ (67%) | 103Cd | rowspan=2|(1/2−) | rowspan=2| | rowspan=2| |- | IT (33%) | 103In |-id=Indium-104 | 104In | style="text-align:right" | 49 | style="text-align:right" | 55 | 103.9182145(62) | 1.80(3) min | β+ | 104Cd | (5+)
|-id=Indium-104m | rowspan=2 style="text-indent:1em" | 104mIn | rowspan=2 colspan="3" style="text-indent:2em" | 93.48(10) keV | rowspan=2|15.7(5) s | ИП (80%) | 104In | rowspan=2|(3+) | rowspan=2| | rowspan=2| |- | β+ (20%) | 104Cd |-id=Indium-105 | 105In | style="text-align:right" | 49 | style="text-align:right" | 56 | 104.914502(11) | 5.07(7) min | β+ | 105Cd | 9/2+
|-id=Indium-105m | rowspan=2 style="text-indent:1em" | 105mIn | rowspan=2 colspan="3" style="text-indent:2em" | 674.09(25) keV | rowspan=2|48(6) s | ИП | 105In | rowspan=2|(1/2)− | rowspan=2| | rowspan=2| |- | β+? | 105Cd |-id=Indium-106 | 106In | style="text-align:right" | 49 | style="text-align:right" | 57 | 105.9134636(13) | 6.2(1) min | β+ | 106Cd | 7+
|-id=Indium-106m | style="text-indent:1em" | 106mIn | colspan="3" style="text-indent:2em" | 28.6(3) keV | 5.2(1) min | β+ | 106Cd | (2)+
|-id=Indium-107 | 107In | style="text-align:right" | 49 | style="text-align:right" | 58 | 106.910287(10) | 32.4(3) min | β+ | 107Cd | 9/2+
|-id=Indium-107m | style="text-indent:1em" | 107mIn | colspan="3" style="text-indent:2em" | 678.5(3) keV | 50.4(6) s | ИП | 107In | 1/2−
|-id=Indium-108 | 108In | style="text-align:right" | 49 | style="text-align:right" | 59 | 107.9096937(93) | 58.0(12) min | β+ | 108Cd | 7+
|-id=Indium-108m | style="text-indent:1em" | 108mIn | colspan="3" style="text-indent:2em" | 29.75(5) keV | 39.6(7) min | β+ | 108Cd | 2+
|-id=Indium-109 | 109In | style="text-align:right" | 49 | style="text-align:right" | 60 | 108.9071497(43) | 4.159(10) h | β+ | 109Cd | 9/2+
|-id=Indium-109m1 | style="text-indent:1em" | 109m1In | colspan="3" style="text-indent:2em" | 649.79(10) keV | 1.34(6) min | ИП | 109In | 1/2−
|-id=Indium-109m2 | style="text-indent:1em" | 109m2In | colspan="3" style="text-indent:2em" | 2101.86(11) keV | 210.0(9) ms | ИП | 109In | 19/2+
|-id=Indium-110 | 110In | style="text-align:right" | 49 | style="text-align:right" | 61 | 109.907171(12) | 4.92(8) h | β+ | 110Cd | 7+
|-id=Indium-110m | style="text-indent:1em" | 110mIn | colspan="3" style="text-indent:2em" | 62.08(4) keV | 69.1(5) min | β+ | 110Cd | 2+
| 111InСе употребува во јадрената медицина | style="text-align:right" | 49 | style="text-align:right" | 62 | 110.9051072(37) | 2.8048(1) d | ЕЗ | 111Cd | 9/2+
|-id=Indium-111m | style="text-indent:1em" | 111mIn | colspan="3" style="text-indent:2em" | 536.99(7) keV | 7.7(2) min | ИП | 111In | 1/2−
|-id=Indium-112 | rowspan=2|112In | rowspan=2 style="text-align:right" | 49 | rowspan=2 style="text-align:right" | 63 | rowspan=2|111.9055387(46) | rowspan=2|14.88(15) min | β+ (62%) | 112Cd | rowspan=2|1+ | rowspan=2| | rowspan=2| |- | β− (38%) | 112Sn |-id=Indium-112m1 | style="text-indent:1em" | 112m1In | colspan="3" style="text-indent:2em" | 156.592(25) keV | 20.67(8) min | ИП | 112In | 4+
|-id=Indium-112m2 | style="text-indent:1em" | 112m2In | colspan="3" style="text-indent:2em" | 350.80(5) keV | 690(50) ns | ИП | 112In | (7)+
|-id=Indium-112m3 | style="text-indent:1em" | 112m3In | colspan="3" style="text-indent:2em" | 613.82(6) keV | 2.81(3) μs | ИП | 112In | 8−
|-id=Indium-113 | 113InFission product | style="text-align:right" | 49 | style="text-align:right" | 64 | 112.90406045(20) | colspan=3 align=center|Stable | 9/2+ | 0.04281(52) | |-id=Indium-113m | style="text-indent:1em" | 113mIn | colspan="3" style="text-indent:2em" | 391.699(3) keV | 1.6579(4) h | ИП | 113In | 1/2−
|-id=Indium-114 | rowspan=2|114In | rowspan=2 style="text-align:right" | 49 | rowspan=2 style="text-align:right" | 65 | rowspan=2|113.90491641(32) | rowspan=2|71.9(1) s | β− (99.50%) | 114Sn | rowspan=2|1+ | rowspan=2| | rowspan=2| |- | β+ (0.50%) | 114Cd |-id=Indium-114m1 | rowspan=2 style="text-indent:1em" | 114m1In | rowspan=2 colspan="3" style="text-indent:2em" | 190.2682(8) keV | rowspan=2|49.51(1) d | ИП (96.75%) | 114In | rowspan=2|5+ | rowspan=2| | rowspan=2| |- | β+ (3.25%) | 114Cd |-id=Indium-114m2 | rowspan=2 style="text-indent:1em" | 114m2In | rowspan=2 colspan="3" style="text-indent:2em" | 501.948(3) keV | rowspan=2|43.1(6) ms | ИП (96.75%) | 114m1In | rowspan=2|8− | rowspan=2| | rowspan=2| |- | β+ (3.25%) | 114Cd |-id=Indium-115 | 115InПрвобитен радионуклид | style="text-align:right" | 49 | style="text-align:right" | 66 | 114.903878772(12) | 4.41(25)×1014 y | β− | 115Sn | 9/2+ | 0.95719(52) | |-id=Indium-115m | rowspan=2 style="text-indent:1em" | 115mIn | rowspan=2 colspan="3" style="text-indent:2em" | 336.244(17) keV | rowspan=2|4.486(4) h | ИП (95.0%) | 115In | rowspan=2|1/2− | rowspan=2| | rowspan=2| |- | β− (5.0%) | 115Sn |-id=Indium-116 | rowspan=2|116In | rowspan=2 style="text-align:right" | 49 | rowspan=2 style="text-align:right" | 67 | rowspan=2|115.90525999(24) | rowspan=2|14.10(3) s | β− (99.98%) | 116Sn | rowspan=2|1+ | rowspan=2| | rowspan=2| |- | EC (0.0237%) | 116Cd |-id=Indium-116m1 | style="text-indent:1em" | 116m1In | colspan="3" style="text-indent:2em" | 127.267(6) keV | 54.29(17) min | β− | 116Sn | 5+
|-id=Indium-116m2 | style="text-indent:1em" | 116m2In | colspan="3" style="text-indent:2em" | 289.660(6) keV | 2.18(4) s | ИП | 116m1In | 8−
|-id=Indium-117 | 117In | style="text-align:right" | 49 | style="text-align:right" | 68 | 116.9045157(52) | 43.2(3) min | β− | 117Sn | 9/2+
|-id=Indium-117m | rowspan=2 style="text-indent:1em" | 117mIn | rowspan=2 colspan="3" style="text-indent:2em" | 315.303(11) keV | rowspan=2|116.2(3) min | β− (52.9%) | 117Sn | rowspan=2|1/2− | rowspan=2| | rowspan=2| |- | ИП (47.1%) | 117In |-id=Indium-118 | 118In | style="text-align:right" | 49 | style="text-align:right" | 69 | 117.9063567(83) | 5.0(5) s | β− | 118Sn | 1+
|-id=Indium-118m1 | style="text-indent:1em" | 118m1In | colspan="3" style="text-indent:2em" | 100(50)# keV | 4.364(7) min | β− | 118Sn | 5+
|-id=Indium-118m2 | rowspan=2 style="text-indent:1em" | 118m2In | rowspan=2 colspan="3" style="text-indent:2em" | 240(50)# keV | rowspan=2|8.5(3) s | ИП (98.6%) | 118m1In | rowspan=2|8− | rowspan=2| | rowspan=2| |- | β− (1.4%) | 118Sn |-id=Indium-119 | 119In | style="text-align:right" | 49 | style="text-align:right" | 70 | 118.9058516(78) | 2.4(1) min | β− | 119Sn | 9/2+
|-id=Indium-119m1 | rowspan=2 style="text-indent:1em" | 119m1In | rowspan=2 colspan="3" style="text-indent:2em" | 311.37(3) keV | rowspan=2|18.0(3) min | β− (97.4%) | 119Sn | rowspan=2|1/2− | rowspan=2| | rowspan=2| |- | ИП (2.6%) | 119In |-id=Indium-119m2 | style="text-indent:1em" | 119m2In | colspan="3" style="text-indent:2em" | 654.27(7) keV | 130(15) ns | IT | 119In | (3/2)+
|-id=Indium-119m3 | style="text-indent:1em" | 119m3In | colspan="3" style="text-indent:2em" | 2656.9(18) keV | 265(10) ns | ИП | 119In | (25/2+)
|-id=Indium-120 | 120In | style="text-align:right" | 49 | style="text-align:right" | 71 | 119.9079875(33) | 3.08(8) s | β− | 120Sn | 1+
|-id=Indium-120m1 | style="text-indent:1em" | 120m1In | colspan="3" style="text-indent:2em" | 90.1(26) keV | 46.2(8) s | β− | 120Sn | 5+
|-id=Indium-120m2 | style="text-indent:1em" | 120m2InOrder of isomers is uncertain. | colspan="3" style="text-indent:2em" | 90.1(26) keV | 47.3(5) s | β− | 120Sn | 8−
|-id=Indium-121 | 121In | style="text-align:right" | 49 | style="text-align:right" | 72 | 120.9078416(13) | 23.1(6) s | β− | 121Sn | 9/2+
|-id=Indium-121m1 | rowspan=2 style="text-indent:1em" | 121m1In | rowspan=2 colspan="3" style="text-indent:2em" | 313.68(7) keV | rowspan=2|3.88(10) min | β− (98.8%) | 121Sn | rowspan=2|1/2− | rowspan=2| | rowspan=2| |- | ИП (1.2%) | 121In |-id=Indium-121m2 | style="text-indent:1em" | 121m2In