Pounds to Kilograms Converter

1 pound is exactly 0.45359237 kilograms. To convert pounds to kilograms, multiply by 0.45359237.

Sources: NIST SP 811, NIST Handbook 44, BIPM SI Brochure Updated October 12, 2026

Result

1 lb = 0.453592 kg

Precision

How to convert pounds to kilograms

kilograms = pounds × 0.45359237

1 pound is exactly 0.45359237 kilogram. The kilogram is the SI base unit of mass.

The factor 0.45359237 is exact, not a rounded value. Nothing is rounded until you choose how many decimals to show.

Worked example: 150 lb

Start with the value in pounds: 150 lb.
Multiply by 0.45359237, because 1 pound = 0.45359237 kilograms: 150 × 0.45359237 = 68.0388555 kg.
Round to the precision you need: 68.04 kg to two decimals.

Pounds and kilograms side by side

Pounds on top, kilograms below, lined up with the exact factor. The line marks the value in the converter. Drawn to proportion, not to actual size.

Pounds to kilograms chart

Pounds from 1 to 100 converted to kilograms with the exact factor, shown to five significant digits.

Pounds to kilograms, part 1 of 4
lb	kg
1	0.45359
2	0.90718
3	1.3608
4	1.8144
5	2.268
6	2.7216
7	3.1751
8	3.6287
9	4.0823
10	4.5359
11	4.9895
12	5.4431
13	5.8967
14	6.3503
15	6.8039
16	7.2575
17	7.7111
18	8.1647
19	8.6183
20	9.0718
21	9.5254
22	9.979
23	10.433
24	10.886
25	11.34

Pounds to kilograms, part 2 of 4
lb	kg
26	11.793
27	12.247
28	12.701
29	13.154
30	13.608
31	14.061
32	14.515
33	14.969
34	15.422
35	15.876
36	16.329
37	16.783
38	17.237
39	17.69
40	18.144
41	18.597
42	19.051
43	19.504
44	19.958
45	20.412
46	20.865
47	21.319
48	21.772
49	22.226
50	22.68

Pounds to kilograms, part 3 of 4
lb	kg
51	23.133
52	23.587
53	24.04
54	24.494
55	24.948
56	25.401
57	25.855
58	26.308
59	26.762
60	27.216
61	27.669
62	28.123
63	28.576
64	29.03
65	29.484
66	29.937
67	30.391
68	30.844
69	31.298
70	31.751
71	32.205
72	32.659
73	33.112
74	33.566
75	34.019

Pounds to kilograms, part 4 of 4
lb	kg
76	34.473
77	34.927
78	35.38
79	35.834
80	36.287
81	36.741
82	37.195
83	37.648
84	38.102
85	38.555
86	39.009
87	39.463
88	39.916
89	40.37
90	40.823
91	41.277
92	41.73
93	42.184
94	42.638
95	43.091
96	43.545
97	43.998
98	44.452
99	44.906
100	45.359

kilograms = pounds × 0.45359237. Factors: NIST SP 811, NIST Handbook 44, BIPM SI Brochure. unitcheck.net/weight/pounds-to-kilograms/

Common values

Pounds	Kilograms	What it is
1 lb	0.453592 kg
10 lb	4.53592 kg
50 lb	22.6796 kg
100 lb	45.3592 kg
150 lb	68.0389 kg
200 lb	90.7185 kg

A quick estimate

Dividing pounds by 2.2 gives a result 0.21% too high: 150 lb ÷ 2.2 = 68.18 kg, against the exact 68.04 kg. Fine for a rough check, not for anything you record.

Going the other way? Use the Kilograms to Pounds converter.

Frequently asked questions

How many kilograms are in 1 pound?

1 pound is exactly 0.45359237 kilograms. 1 pound is exactly 0.45359237 kilogram.

How do I convert pounds to kilograms?

Multiply by 0.45359237: kilograms = pounds × 0.45359237. For example, 150 lb = 68.04 kg.

How many pounds are in 1 kilogram?

1 kilogram is about 2.20462 pounds. To go the other way, use the kilograms to pounds converter.

Is the lb to kg conversion exact?

Yes. 1 pound is exactly 0.45359237 kilogram. The factor 0.45359237 follows from the definitions, so the only rounding is in the number of decimals you display.

Sources

NIST Special Publication 811, Guide for the Use of the International System of Units, Appendix B.8: Factors for Units Listed Alphabetically — exact factors are printed in bold in the NIST table (checked October 12, 2026)
NIST Handbook 44 (2026), Appendix C: General Tables of Units of Measurement — US customary units and their exact relationships (checked October 12, 2026)
BIPM, The International System of Units (SI Brochure), 9th edition — defines the SI units, the prefixes and the units accepted for use with the SI