Антимонот (Sb) се јавува во два стабилни изотопи, Sb и Sb. Постојат 37 вештачки радиоактивни изотопи, од кои најдолговечни се Sb, со време на полураспад од 2,75856 години; Sb, со време на полураспад 60,2 дена и Sb, со време на полураспад 12,35 дена. Сите други изотопи имаат време на полураспад помалку од 4 дена, повеќето помалку од еден час. Има и многу изомери, од кои најдолготрајниот е Sb со време на полураспад 5,76 дена.
Освен берилиумот, антимонот е најлесниот елемент забележан дека има изотопи способни за алфа-распаѓање. Sb се гледа дека е подложен на овој начин на распаѓање. Некои светлосни елементи, имено оние во близина на Be, имаат изотопи со одложена алфа-емисија (по протонска или бета-емисија) како ретка гранка.
Список на изотопи
|-id=Антимон-104 | rowspan=4|104Sb | rowspan=4 style="text-align:right" | 51 | rowspan=4 style="text-align:right" | 53 | rowspan=4|103,93634(11)# | rowspan=4|470(130) мс | β+? | 104Sn | rowspan=4| | rowspan=4| | rowspan=4| |- | p (<7%) | 103Sn |- | β+, p (<7%) | 103In |- | α? | 100In |-id=Антимон-105 | rowspan=3|105Sb | rowspan=3 style="text-align:right" | 51 | rowspan=3 style="text-align:right" | 54 | rowspan=3|104,931277(23) | rowspan=3|1,12(16) с | β+ (>99,9%) | 105Sn | rowspan=3|(5/2+) | rowspan=3| | rowspan=3| |- | p (<0,1%) | 104Sn |- | β+, p? | 104In |-id=Антимон-106 | 106Sb | style="text-align:right" | 51 | style="text-align:right" | 55 | 105,9286380(80) | 0,6(2) с | β+ | 106Sn | (2+)
|-id=Антимон-106m | style="text-indent:1em" | 106mSb | colspan="3" style="text-indent:2em" | 103,5(3) keV | 226(14) нс | IT | 106Sb | (4+)
|-id=Антимон-107 | 107Sb | style="text-align:right" | 51 | style="text-align:right" | 56 | 106,9241506(45) | 4,0(2) с | β+ | 107Sn | 5/2+#
|-id=Антимон-108 | 108Sb | style="text-align:right" | 51 | style="text-align:right" | 57 | 107,9222267(59) | 7,4(3) с | β+ | 108Sn | (4+)
|-id=Антимон-109 | 109Sb | style="text-align:right" | 51 | style="text-align:right" | 58 | 108,9181412(57) | 17,2(5) с | β+ | 109Sn | 5/2+#
|-id=Антимон-110 | 110Sb | style="text-align:right" | 51 | style="text-align:right" | 59 | 109,9168543(64) | 23,6(3) с | β+ | 110Sn | (3+)
|-id=Антимон-111 | 111Sb | style="text-align:right" | 51 | style="text-align:right" | 60 | 110,9132182(95) | 75(1) с | β+ | 111Sn | (5/2+)
|-id=Антимон-112 | 112Sb | style="text-align:right" | 51 | style="text-align:right" | 61 | 111,912400(19) | 53,5(6) с | β+ | 112Sn | (3+)
|-id=Антимон-112m | style="text-indent:1em" | 112mSb | colspan="3" style="text-indent:2em" | 825,9(4) keV | 536(22) нс | IT | 112Sb | (8−)
|-id=Антимон-113 | 113Sb | style="text-align:right" | 51 | style="text-align:right" | 62 | 112,909375(18) | 6,67(7) мин | β+ | 113Sn | 5/2+
|-id=Антимон-114 | 114Sb | style="text-align:right" | 51 | style="text-align:right" | 63 | 113,909289(21) | 3,49(3) мин | β+ | 114Sn | 3+
|-id=Антимон-114m | style="text-indent:1em" | 114mSb | colspan="3" style="text-indent:2em" | 495,5(7) keV | 219(12) μс | IT | 114Sb | (8−)
|-id=Антимон-115 | 115Sb | style="text-align:right" | 51 | style="text-align:right" | 64 | 114,906598(17) | 32,1(3) мин | β+ | 115Sn | 5/2+
|-id=Антимон-115m | style="text-indent:1em" | 115mSb | colspan="3" style="text-indent:2em" | 2796,26(9) keV | 159(3) нс | IT | 115Sb | (19/2)−
|-id=Антимон-116 | 116Sb | style="text-align:right" | 51 | style="text-align:right" | 65 | 115,9067927(55) | 15,8(8) мин | β+ | 116Sn | 3+
|-id=Антимон-116m1 | style="text-indent:1em" | 116m1Sb | colspan="3" style="text-indent:2em" | 93,99(5) keV | 194(4) нс | IT | 116Sb | 1+
|-id=Антимон-116m2 | style="text-indent:1em" | 116m2Sb | colspan="3" style="text-indent:2em" | 390(40) keV | 60,3(6) мин | β+ | 116Sn | 8−
|-id=Антимон-117 | 117Sb | style="text-align:right" | 51 | style="text-align:right" | 66 | 116,9048415(91) | 2,97(2) h | β+ | 117Sn | 5/2+
|-id=Антимон-117m1 | style="text-indent:1em" | 117m1Sb | colspan="3" style="text-indent:2em" | 3130,76(19) keV | 355(17) μс | IT | 117Sb | (25/2)+
|-id=Антимон-117m2 | style="text-indent:1em" | 117m2Sb | colspan="3" style="text-indent:2em" | 3230,7(2) keV | 290(5) нс | IT | 117Sb | (23/2−)
|-id=Антимон-118 | 118Sb | style="text-align:right" | 51 | style="text-align:right" | 67 | 117,9055322(32) | 3,6(1) мин | β+ | 118Sn | 1+
|-id=Антимон-118m1 | style="text-indent:1em" | 118m1Sb | colspan="3" style="text-indent:2em" | 50,814(21) keV | 20,6(6) μс | IT | 118Sb | 3+
|-id=Антимон-118m2 | style="text-indent:1em" | 118m2Sb | colspan="3" style="text-indent:2em" | 250(6) keV | 5,01(3) h | β+ | 118Sn | 8−
|-id=Антимон-119 | 119Sb | style="text-align:right" | 51 | style="text-align:right" | 68 | 118,9039441(75) | 38,19(22) h | EC | 119Sn | 5/2+
|-id=Антимон-119m1 | style="text-indent:1em" | 119m1Sb | colspan="3" style="text-indent:2em" | 2553,6(3) keV | 130(3) нс | IT | 119Sb | 19/2−
|-id=Антимон-119m2 | style="text-indent:1em" | 119m2Sb | colspan="3" style="text-indent:2em" | 2841,7(4) keV | 835(81) мс | IT | 119Sb | 25/2+
|-id=Антимон-120 | 120Sb | style="text-align:right" | 51 | style="text-align:right" | 69 | 119,9050803(77) | 15,89(4) мин | β+ | 120Sn | 1+
|-id=Антимон-120m1 | style="text-indent:1em" | 120m1SbРедоследот на основната состојба и изомерот е неизвесен. | colspan="3" style="text-indent:2em" | 0(100)# keV | 5,76(2) д | β+ | 120Sn | 8−
|-id=Антимон-120m2 | style="text-indent:1em" | 120m2Sb | colspan="3" style="text-indent:2em" | 78,16(5) keV | 246(2) нс | IT | 120Sb | (3+)
|-id=Антимон-120m3 | style="text-indent:1em" | 120m3Sb | colspan="3" style="text-indent:2em" | 2328(100)# keV | 400(8) нс | IT | 120Sb | 13+
|-id=Антимон-121 | 121SbФисионен производ | style="text-align:right" | 51 | style="text-align:right" | 70 | 120,9038114(27) | colspan=3 align=center|Stable | 5/2+ | 0,5721(5) | |-id=Антимон-121m | style="text-indent:1em" | 121mSb | colspan="3" style="text-indent:2em" | 2751(17) keV | 179(6) μс | IT | 121Sb | (25/2+)
|-id=Антимон-122 | rowspan=2|122Sb | rowspan=2 style="text-align:right" | 51 | rowspan=2 style="text-align:right" | 71 | rowspan=2|121,9051693(27) | rowspan=2|2,7238(2) д | β− (97,59%) | 122Te | rowspan=2|2− | rowspan=2| | rowspan=2| |- | β+ (2,41%) | 122Sn |-id=Антимон-122m1 | style="text-indent:1em" | 122m1Sb | colspan="3" style="text-indent:2em" | 61,4131(5) keV | 1,86(8) μс | IT | 122Sb | 3+
|-id=Антимон-122m2 | style="text-indent:1em" | 122m2Sb | colspan="3" style="text-indent:2em" | 137,4726(8) keV | 0,53(3) мс | IT | 122Sb | 5+
|-id=Антимон-122m3 | style="text-indent:1em" | 122m3Sb | colspan="3" style="text-indent:2em" | 163,5591(17) keV | 4,191(3) мин | IT | 122Sb | 8−
|-id=Антимон-123 | 123Sb | style="text-align:right" | 51 | style="text-align:right" | 72 | 122,9042153(15) | colspan=3 align=center|Stable | 7/2+ | 0,4279(5) | |-id=Антимон-123m1 | style="text-indent:1em" | 123m1Sb | colspan="3" style="text-indent:2em" | 2237,8(3) keV | 214(3) нс | IT | 123Sb | 19/2−
|-id=Антимон-123m2 | style="text-indent:1em" | 123m2Sb | colspan="3" style="text-indent:2em" | 2613,4(4) keV | 65(1) μс | IT | 123Sb | 23/2+
|-id=Антимон-124 | 124Sb | style="text-align:right" | 51 | style="text-align:right" | 73 | 123,9059371(15) | 60,20(3) д | β− | 124Te | 3−
|-id=Антимон-124m1 | rowspan=2 style="text-indent:1em" | 124m1Sb | rowspan=2 colspan="3" style="text-indent:2em" | 10,8627(8) keV | rowspan=2|93(5) с | IT (75%) | 124Sb | rowspan=2|5+ | rowspan=2| | rowspan=2| |- | β− (25%) | 124Te |-id=Антимон-124m2 | style="text-indent:1em" | 124m2Sb | colspan="3" style="text-indent:2em" | 36,8440(14) keV | 20,2(2) мин | IT | 124m1Sb | (8)−
|-id=Антимон-124m3 | style="text-indent:1em" | 124m3Sb | colspan="3" style="text-indent:2em" | 40,8038(7) keV | 3,2(3) μс | IT | 124Sb | (3+)
|-id=Антимон-125 | 125Sb | style="text-align:right" | 51 | style="text-align:right" | 74 | 124,9052543(27) | 2,7576(11) г | β− | 125Te | 7/2+
|-id=Антимон-125m1 | style="text-indent:1em" | 125m1Sb | colspan="3" style="text-indent:2em" | 1971,25(20) keV | 4,1(2) μс | IT | 125Sb | 15/2−
|-id=Антимон-125m2 | style="text-indent:1em" | 125m2Sb | colspan="3" style="text-indent:2em" | 2112,1(3) keV | 28,5(5) μс | IT | 125Sb | 19/2−
|-id=Антимон-125m3 | style="text-indent:1em" | 125m3Sb | colspan="3" style="text-indent:2em" | 2471,0(4) keV | 277,0(64) нс | IT | 125Sb | (23/2)+
|-id=Антимон-126 | 126Sb | style="text-align:right" | 51 | style="text-align:right" | 75 | 125,907253(34) | 12,35(6) д | β− | 126Te | 8−
|-id=Антимон-126m1 | rowspan=2 style="text-indent:1em" | 126m1Sb | rowspan=2 colspan="3" style="text-indent:2em" | 17,7(3) keV | rowspan=2|19,15(8) мин | β− (86%) | 126Te | rowspan=2|5+ | rowspan=2| | rowspan=2| |- | IT (14%) | 126Sb |-id=Антимон-126m2 | style="text-indent:1em" | 126m2Sb | colspan="3" style="text-indent:2em" | 40,4(3) keV | ~11 с | IT | 126m1Sb | 3−
|-id=Антимон-126m3 | style="text-indent:1em" | 126m3Sb | colspan="3" style="text-indent:2em" | 104,6(3) keV | 553(5) нс | IT | 126Sb | 3+
|-id=Антимон-126m4 | style="text-indent:1em" | 126m4Sb | colspan="3" style="text-indent:2em" | 1810,7(17) keV | 90(16) нс | IT | 126Sb | (13+)
|-id=Антимон-127 | 127Sb | style="text-align:right" | 51 | style="text-align:right" | 76 | 126,9069256(55) | 3,85(5) д | β− | 127Te | 7/2+
|-id=Антимон-127m1 | style="text-indent:1em" | 127m1Sb | colspan="3" style="text-indent:2em" | 1920,19(21) keV | 11,7(1) μс | IT | 127Sb | 15/2−
|-id=Антимон-127m2 | style="text-indent:1em" | 127m2Sb | colspan="3" style="text-indent:2em" | 2324,7(4) keV | 269(5) нс | IT | 127Sb | 23/2+
|-id=Антимон-128 | 128Sb | style="text-align:right" | 51 | style="text-align:right" | 77 | 127,909146(20) | 9,05(4) h | β− | 128Te | 8−
|-id=Антимон-128m1 | rowspan=2 style="text-indent:1em" | 128m1Sb | rowspan=2 colspan="3" style="text-indent:2em" | 10(6) keV | rowspan=2|10,41(18) мин | β− (96,4%) | 128Te | rowspan=2|5+ | rowspan=2| | rowspan=2| |- | IT (3,6%) | 128Sb |-id=Антимон-128m2 | style="text-indent:1em" | 128m2Sb | colspan="3" style="text-indent:2em" | 1617,3(7) keV | 500(20) нс | IT | 128Sb | (11+)
|-id=Антимон-128m3 | style="text-indent:1em" | 128m3Sb | colspan="3" style="text-indent:2em" | 1769,9(12) keV | 217(7) нс | IT | 128Sb | (13+)
|-id=Антимон-129 | 129Sb | style="text-align:right" | 51 | style="text-align:right" | 78 | 128,909147(23) | 4,366(26) h | β− | 129Te | 7/2+
|-id=Антимон-129m1 | rowspan=2 style="text-indent:1em" | 129m1Sb | rowspan=2 colspan="3" style="text-indent:2em" | 1851,31(6) keV | rowspan=2|17,7(1) мин | β− (85%) | 129Te | rowspan=2|19/2− | rowspan=2| | rowspan=2| |- | IT (15%) | 129Sb |-id=Антимон-129m2 | style="text-indent:1em" | 129m2Sb | colspan="3" style="text-indent:2em" | 1861,06(5) keV | 2,23(17) μс | IT | 129Sb | 15/2−
|-id=Антимон-129m3 | style="text-indent:1em" | 129m3Sb | colspan="3" style="text-indent:2em" | 2139,4(3) keV | 0,89(3) μс | IT | 129Sb | 23/2+
|-id=Антимон-130 | 130Sb | style="text-align:right" | 51 | style="text-align:right" | 79 | 129,911663(15) | 39,5(8) мин | β− | 130Te | 8−
|-id=Антимон-130m1 | style="text-indent:1em" | 130m1Sb | colspan="3" style="text-indent:2em" | 4,80(20) keV | 6,3(2) мин | β− | 130Te | 4+
|-id=Антимон-130m2 | style="text-indent:1em" | 130m2Sb | colspan="3" style="text-indent:2em" | 84,67(4) keV | 800(100) нс | IT | 130Sb | 6−
|-id=Антимон-130m3 | style="text-indent:1em" | 130m3Sb | colspan="3" style="text-indent:2em" | 1508(1) keV | 600(15) нс | IT | 130Sb | (11+)
|-id=Антимон-130m4 | style="text-indent:1em" | 130m4Sb | colspan="3" style="text-indent:2em" | 1544,7(5) keV | 1,25(1) μс | IT | 130Sb | (13+)
|-id=Антимон-131 | 131Sb | style="text-align:right" | 51 | style="text-align:right" | 80 | 130,9119893(22) | 23,03(4) мин | β− | 131Te | 7/2+
|-id=Антимон-131m1 | style="text-indent:1em" | 131m1Sb | colspan="3" style="text-indent:2em" | 1676,06(6) keV | 64,2(26) μс | IT | 131Sb | 15/2−
|-id=Антимон-131m2 | style="text-indent:1em" | 131m2Sb | colspan="3" style="text-indent:2em" | 1687,2(9) keV | 4,3(8) μс | IT | 131Sb | 19/2−