Table of Atomic Weights of Elements in the Periodic Table

The atomic weight of an atom is the total weight of an atom. It is also called relative atomic mass.

In the following table, the atomic weights of all the Periodic Table elements are given based on carbon 12 = 12.0000. The numbers in the parentheses represent the mass numbers of the most stable known isotope.

Table of Atomic Weights of All the Elements in the Periodic Table

Atomic Number	Symbol	Atom Name	Relative Atomic Mass (Atomic Weight)
1	H	Hydrogen	1.00797
2	He	Helium	4.003
3	Li	Lithium	6.939
4	Be	Beryllium	9.012
5	B	Boron	10.811
6	C	Carbon	12.01115
7	N	Nitrogen	14.0067
8	O	Oxygen	15.9994
9	F	Fluorine	18.993
10	Ne	Neon	20.183
11	Na	Sodium	22.9898
12	Mg	Magnesium	24.312
13	Al	Aluminium	26.982
14	Si	Silicon	28.086
15	P	Phosphorus	30.9738
16	S	Sulfur	32.064
17	Cl	Chlorine	35.453
18	Ar	Argon	39.948
19	K	Potassium	39.102
20	Ca	Calcium	40.08
21	Sc	Scandium	44.96
22	Ti	Titanium	47.90
23	V	Vanadium	50.942
24	Cr	Chromium	51.996
25	Mn	Manganese	54.938
26	Fe	Iron	55.847
27	Co	Cobalt	58.933
28	Ni	Nickel	58.71
29	Cu	Copper	63.54
30	Zn	Zinc	65.39(2)
31	Ga	Gallium	69.723(4)
32	Ge	Germanium	72.61(2)
33	As	Arsenic	74.921 59(2)
34	Se	Selenium	78.96(3)
35	Br	Bromine	79.904(1)
36	Kr	Krypton	83.80(1)
37	Rb	Rubidium	85.467 8(3)
38	Sr	Strontium	87.62(1)
39	Y	Yttrium	88.905 85(2)
40	Zr	Zirconium	91.224(2)
41	Nb	Niobium	92.906 38(2)
42	Mo	Molybdenum	95.94(1)
43	Tc	Technetium	[99]*
44	Ru	Ruthenium	101.07(2)
45	Rh	Rhodium	102.905 50(3)
46	Pd	Palladium	106.42(1)
47	Ag	Silver	107.868 2(2)
48	Cd	Cadmium	112.411(8)
49	In	Indium	114.82(1)
50	Sn	Tin	118.710(7)
51	Sb	Antimony	121.75(3)
52	Te	Tellurium	127.60(3)
53	I	Iodine	126.904 47(3)
54	Xe	Xenon	131.29(2)
55	Cs	Caesium	132.905 43(5)
56	Ba	Barium	137.327(7)
57	La	Lanthanum	138.905 5(2)
58	Ce	Cerium	140.115(4)
59	Pr	Praseodymium	140.907 65(3)
60	Nd	Neodymium	144.24(3)
61	Pm	Promethium	[147]*
62	Sm	Samarium	150.36(3)
63	Eu	Europium	151.965(9)
64	Gd	Gadolinium	157.25(3)
65	Tb	Terbium	158.925 34(3)
66	Dy	Dysprosium	162.50(3)
67	Ho	Holmium	164.930 32(3)
68	Er	Erbium	167.26(3)
69	Tm	Thulium	168.934 21(3)
70	Yb	Ytterbium	173.04(3)
71	Lu	Lutetium	174.967(1)
72	Hf	Hafnium	178.49(2)
73	Ta	Tantalum	180.947 9(1)
74	W	Tungsten	183.85(3)
75	Re	Rhenium	186.207(1)
76	Os	Osmium	190.2(1)
77	Ir	Iridium	192.22(3)
78	Pt	Platinum	195.08(3)
79	Au	Gold	196.966 54(3)
80	Hg	Mercury	200.59(3)
81	Tl	Thallium	204.383 3(2)
82	Pb	Lead	207.2(1)
83	Bi	Bismuth	208.980 37(3)
84	Po	Polonium	[210]*
85	At	Astatine	[210]*
86	Rn	Radon	[222]*
87	Fr	Francium	[223]*
88	Ra	Radium	[226]*
89	Ac	Actinium	[227]*
90	Th	Thorium	232.038 1(1)
91	Pa	Protactinium	231.035 88(2)
92	U	Uranium	238.028 9(1)
93	Np	Neptunium	[237]*
94	Pu	Plutonium	[244]*
95	Am	Americium	[243]*
96	Cm	Curium	[247]*
97	Bk	Berkelium	[247]*
98	Cf	Californium	[251]*
99	Es	Einsteinium	[252]*
100	Fm	Fermium	[257]*
101	Md	Mendelevium	[258]*
102	No	Nobelium	[259]*
103	Lr	Lawrencium	[262]*
104	Rf	Rutherfordium	[267]*
105	Db	Dubnium	[270]*
106	Sg	Seaborgium	[269]*
107	Bh	Bohrium	[270]*
108	Hs	Hassium	[270]*
109	Mt	Meitnerium	[278]*
110	Ds	Darmstadtium	[281]*
111	Rg	Roentgenium	[281]*
112	Cn	Copernicium	[285]*
113	Nh	Nihonium	[286]*
114	Fl	Flerovium	[289]*
115	Mc	Moscovium	[289]*
116	Lv	Livermorium	[293]*
117	Ts	Tennessine	[293]*
118	Og	Oganesson	[294]*

Reference:

1. Pure Appl. Chem. 52 (1980) 2349-2384
2. Pure Appl. Chem. 56, (1984) 695-768
3. Pure Appl. Chem. 58 (1986) 1677-1692
4. Pure Appl. Chem. 56 (1984) 675-694
5. IUPAC: Pure and Applied Chemistry (1994) 66, 2433-2444.