How to convert pounds-force to newtons
Multiply the value in pounds-force by 4.4482. The hard part is not the arithmetic but the reading: an American datasheet often writes lb for a force as well as for a mass, and only the surrounding sentence says which one is meant.
Where these two units are used
The pound-force is what a pound weighs under standard gravity, and it is the unit of American engineering, where a jet engine's thrust runs into thousands of them. The newton is the force that gives one kilogram an acceleration of one meter per second squared, and it has borne that name only since 1948.
Everyday forces in pounds-force and in newtons
| 1 lbf | 4.45 N |
| 2 lbf | 8.90 N |
| 5 lbf (door) | 22.24 N |
| 10 lbf | 44.48 N |
| 20 lbf | 88.96 N |
| 40 lbf (bow) | 177.93 N |
| 50 lbf | 222.41 N |
| 100 lbf | 444.82 N |
| 500 lbf | 2,224.11 N |
| 1,000 lbf | 4,448.22 N |
| 5,000 lbf | 22,241.11 N |
Show every value
- 1 lbf = 4.448 N
- 2 lbf = 8.896 N
- 3 lbf = 13.345 N
- 4 lbf = 17.793 N
- 5 lbf = 22.241 N
- 6 lbf = 26.689 N
- 7 lbf = 31.138 N
- 8 lbf = 35.586 N
- 9 lbf = 40.034 N
- 10 lbf = 44.482 N
- 11 lbf = 48.93 N
- 12 lbf = 53.379 N
- 13 lbf = 57.827 N
- 14 lbf = 62.275 N
- 15 lbf = 66.723 N
- 16 lbf = 71.172 N
- 17 lbf = 75.62 N
- 18 lbf = 80.068 N
- 19 lbf = 84.516 N
- 20 lbf = 88.964 N
- 21 lbf = 93.413 N
- 22 lbf = 97.861 N
- 23 lbf = 102.309 N
- 24 lbf = 106.757 N
- 25 lbf = 111.206 N
- 26 lbf = 115.654 N
- 27 lbf = 120.102 N
- 28 lbf = 124.55 N
- 29 lbf = 128.998 N
- 30 lbf = 133.447 N
- 31 lbf = 137.895 N
- 32 lbf = 142.343 N
- 33 lbf = 146.791 N
- 34 lbf = 151.24 N
- 35 lbf = 155.688 N
- 36 lbf = 160.136 N
- 37 lbf = 164.584 N
- 38 lbf = 169.032 N
- 39 lbf = 173.481 N
- 40 lbf = 177.929 N
- 41 lbf = 182.377 N
- 42 lbf = 186.825 N
- 43 lbf = 191.274 N
- 44 lbf = 195.722 N
- 45 lbf = 200.17 N
- 46 lbf = 204.618 N
- 47 lbf = 209.066 N
- 48 lbf = 213.515 N
- 49 lbf = 217.963 N
- 50 lbf = 222.411 N
- 51 lbf = 226.859 N
- 52 lbf = 231.308 N
- 53 lbf = 235.756 N
- 54 lbf = 240.204 N
- 55 lbf = 244.652 N
- 56 lbf = 249.1 N
- 57 lbf = 253.549 N
- 58 lbf = 257.997 N
- 59 lbf = 262.445 N
- 60 lbf = 266.893 N
- 61 lbf = 271.342 N
- 62 lbf = 275.79 N
- 63 lbf = 280.238 N
- 64 lbf = 284.686 N
- 65 lbf = 289.134 N
- 66 lbf = 293.583 N
- 67 lbf = 298.031 N
- 68 lbf = 302.479 N
- 69 lbf = 306.927 N
- 70 lbf = 311.376 N
- 71 lbf = 315.824 N
- 72 lbf = 320.272 N
- 73 lbf = 324.72 N
- 74 lbf = 329.168 N
- 75 lbf = 333.617 N
- 76 lbf = 338.065 N
- 77 lbf = 342.513 N
- 78 lbf = 346.961 N
- 79 lbf = 351.41 N
- 80 lbf = 355.858 N
- 81 lbf = 360.306 N
- 82 lbf = 364.754 N
- 83 lbf = 369.202 N
- 84 lbf = 373.651 N
- 85 lbf = 378.099 N
- 86 lbf = 382.547 N
- 87 lbf = 386.995 N
- 88 lbf = 391.444 N
- 89 lbf = 395.892 N
- 90 lbf = 400.34 N
- 91 lbf = 404.788 N
- 92 lbf = 409.236 N
- 93 lbf = 413.685 N
- 94 lbf = 418.133 N
- 95 lbf = 422.581 N
- 96 lbf = 427.029 N
- 97 lbf = 431.477 N
- 98 lbf = 435.926 N
- 99 lbf = 440.374 N
- 100 lbf = 444.822 N
- 101 lbf = 449.27 N
- 102 lbf = 453.719 N
- 103 lbf = 458.167 N
- 104 lbf = 462.615 N
- 105 lbf = 467.063 N
- 106 lbf = 471.511 N
- 107 lbf = 475.96 N
- 108 lbf = 480.408 N
- 109 lbf = 484.856 N
- 110 lbf = 489.304 N
- 111 lbf = 493.753 N
- 112 lbf = 498.201 N
- 113 lbf = 502.649 N
- 114 lbf = 507.097 N
- 115 lbf = 511.545 N
- 116 lbf = 515.994 N
- 117 lbf = 520.442 N
- 118 lbf = 524.89 N
- 119 lbf = 529.338 N
- 120 lbf = 533.787 N
- 121 lbf = 538.235 N
- 122 lbf = 542.683 N
- 123 lbf = 547.131 N
- 124 lbf = 551.579 N
- 125 lbf = 556.028 N
- 126 lbf = 560.476 N
- 127 lbf = 564.924 N
- 128 lbf = 569.372 N
- 129 lbf = 573.821 N
- 130 lbf = 578.269 N
- 131 lbf = 582.717 N
- 132 lbf = 587.165 N
- 133 lbf = 591.613 N
- 134 lbf = 596.062 N
- 135 lbf = 600.51 N
- 136 lbf = 604.958 N
- 137 lbf = 609.406 N
- 138 lbf = 613.855 N
- 139 lbf = 618.303 N
- 140 lbf = 622.751 N
- 141 lbf = 627.199 N
- 142 lbf = 631.647 N
- 143 lbf = 636.096 N
- 144 lbf = 640.544 N
- 145 lbf = 644.992 N
- 146 lbf = 649.44 N
- 147 lbf = 653.889 N
- 148 lbf = 658.337 N
- 149 lbf = 662.785 N
- 150 lbf = 667.233 N
- 151 lbf = 671.681 N
- 152 lbf = 676.13 N
- 153 lbf = 680.578 N
- 154 lbf = 685.026 N
- 155 lbf = 689.474 N
- 156 lbf = 693.923 N
- 157 lbf = 698.371 N
- 158 lbf = 702.819 N
- 159 lbf = 707.267 N
- 160 lbf = 711.715 N
- 161 lbf = 716.164 N
- 162 lbf = 720.612 N
- 163 lbf = 725.06 N
- 164 lbf = 729.508 N
- 165 lbf = 733.957 N
- 166 lbf = 738.405 N
- 167 lbf = 742.853 N
- 168 lbf = 747.301 N
- 169 lbf = 751.749 N
- 170 lbf = 756.198 N
- 171 lbf = 760.646 N
- 172 lbf = 765.094 N
- 173 lbf = 769.542 N
- 174 lbf = 773.991 N
- 175 lbf = 778.439 N
- 176 lbf = 782.887 N
- 177 lbf = 787.335 N
- 178 lbf = 791.783 N
- 179 lbf = 796.232 N
- 180 lbf = 800.68 N
- 181 lbf = 805.128 N
- 182 lbf = 809.576 N
- 183 lbf = 814.025 N
- 184 lbf = 818.473 N
- 185 lbf = 822.921 N
- 186 lbf = 827.369 N
- 187 lbf = 831.817 N
- 188 lbf = 836.266 N
- 189 lbf = 840.714 N
- 190 lbf = 845.162 N
- 191 lbf = 849.61 N
- 192 lbf = 854.059 N
- 193 lbf = 858.507 N
- 194 lbf = 862.955 N
- 195 lbf = 867.403 N
- 196 lbf = 871.851 N
- 197 lbf = 876.3 N
- 198 lbf = 880.748 N
- 199 lbf = 885.196 N
- 200 lbf = 889.644 N
- 205 lbf = 911.885 N
- 210 lbf = 934.127 N
- 215 lbf = 956.368 N
- 220 lbf = 978.609 N
- 225 lbf = 1,000.85 N
- 230 lbf = 1,023.091 N
- 235 lbf = 1,045.332 N
- 240 lbf = 1,067.573 N
- 245 lbf = 1,089.814 N
- 250 lbf = 1,112.055 N
- 255 lbf = 1,134.297 N
- 260 lbf = 1,156.538 N
- 265 lbf = 1,178.779 N
- 270 lbf = 1,201.02 N
- 275 lbf = 1,223.261 N
- 280 lbf = 1,245.502 N
- 285 lbf = 1,267.743 N
- 290 lbf = 1,289.984 N
- 295 lbf = 1,312.225 N
- 300 lbf = 1,334.466 N
- 305 lbf = 1,356.708 N
- 310 lbf = 1,378.949 N
- 315 lbf = 1,401.19 N
- 320 lbf = 1,423.431 N
- 325 lbf = 1,445.672 N
- 330 lbf = 1,467.913 N
- 335 lbf = 1,490.154 N
- 340 lbf = 1,512.395 N
- 345 lbf = 1,534.636 N
- 350 lbf = 1,556.878 N
- 355 lbf = 1,579.119 N
- 360 lbf = 1,601.36 N
- 365 lbf = 1,623.601 N
- 370 lbf = 1,645.842 N
- 375 lbf = 1,668.083 N
- 380 lbf = 1,690.324 N
- 385 lbf = 1,712.565 N
- 390 lbf = 1,734.806 N
- 395 lbf = 1,757.048 N
- 400 lbf = 1,779.289 N
- 405 lbf = 1,801.53 N
- 410 lbf = 1,823.771 N
- 415 lbf = 1,846.012 N
- 420 lbf = 1,868.253 N
- 425 lbf = 1,890.494 N
- 430 lbf = 1,912.735 N
- 435 lbf = 1,934.976 N
- 440 lbf = 1,957.218 N
- 445 lbf = 1,979.459 N
- 450 lbf = 2,001.7 N
- 455 lbf = 2,023.941 N
- 460 lbf = 2,046.182 N
- 465 lbf = 2,068.423 N
- 470 lbf = 2,090.664 N
- 475 lbf = 2,112.905 N
- 480 lbf = 2,135.146 N
- 485 lbf = 2,157.387 N
- 490 lbf = 2,179.629 N
- 495 lbf = 2,201.87 N
- 500 lbf = 2,224.111 N
- 510 lbf = 2,268.593 N
- 520 lbf = 2,313.075 N
- 530 lbf = 2,357.557 N
- 540 lbf = 2,402.04 N
- 550 lbf = 2,446.522 N
- 560 lbf = 2,491.004 N
- 570 lbf = 2,535.486 N
- 580 lbf = 2,579.969 N
- 590 lbf = 2,624.451 N
- 600 lbf = 2,668.933 N
- 610 lbf = 2,713.415 N
- 620 lbf = 2,757.897 N
- 630 lbf = 2,802.38 N
- 640 lbf = 2,846.862 N
- 650 lbf = 2,891.344 N
- 660 lbf = 2,935.826 N
- 670 lbf = 2,980.308 N
- 680 lbf = 3,024.791 N
- 690 lbf = 3,069.273 N
- 700 lbf = 3,113.755 N
- 710 lbf = 3,158.237 N
- 720 lbf = 3,202.72 N
- 730 lbf = 3,247.202 N
- 740 lbf = 3,291.684 N
- 750 lbf = 3,336.166 N
- 760 lbf = 3,380.648 N
- 770 lbf = 3,425.131 N
- 780 lbf = 3,469.613 N
- 790 lbf = 3,514.095 N
- 800 lbf = 3,558.577 N
- 810 lbf = 3,603.06 N
- 820 lbf = 3,647.542 N
- 830 lbf = 3,692.024 N
- 840 lbf = 3,736.506 N
- 850 lbf = 3,780.988 N
- 860 lbf = 3,825.471 N
- 870 lbf = 3,869.953 N
- 880 lbf = 3,914.435 N
- 890 lbf = 3,958.917 N
- 900 lbf = 4,003.399 N
- 910 lbf = 4,047.882 N
- 920 lbf = 4,092.364 N
- 930 lbf = 4,136.846 N
- 940 lbf = 4,181.328 N
- 950 lbf = 4,225.811 N
- 960 lbf = 4,270.293 N
- 970 lbf = 4,314.775 N
- 980 lbf = 4,359.257 N
- 990 lbf = 4,403.739 N
- 1,000 lbf = 4,448.222 N
- 1,025 lbf = 4,559.427 N
- 1,050 lbf = 4,670.633 N
- 1,075 lbf = 4,781.838 N
- 1,100 lbf = 4,893.044 N
- 1,125 lbf = 5,004.249 N
- 1,150 lbf = 5,115.455 N
- 1,175 lbf = 5,226.66 N
- 1,200 lbf = 5,337.866 N
- 1,225 lbf = 5,449.071 N
- 1,250 lbf = 5,560.277 N
- 1,275 lbf = 5,671.483 N
- 1,300 lbf = 5,782.688 N
- 1,325 lbf = 5,893.894 N
- 1,350 lbf = 6,005.099 N
- 1,375 lbf = 6,116.305 N
- 1,400 lbf = 6,227.51 N
- 1,425 lbf = 6,338.716 N
- 1,450 lbf = 6,449.921 N
- 1,475 lbf = 6,561.127 N
- 1,500 lbf = 6,672.332 N
- 1,525 lbf = 6,783.538 N
- 1,550 lbf = 6,894.744 N
- 1,575 lbf = 7,005.949 N
- 1,600 lbf = 7,117.155 N
- 1,625 lbf = 7,228.36 N
- 1,650 lbf = 7,339.566 N
- 1,675 lbf = 7,450.771 N
- 1,700 lbf = 7,561.977 N
- 1,725 lbf = 7,673.182 N
- 1,750 lbf = 7,784.388 N
- 1,775 lbf = 7,895.593 N
- 1,800 lbf = 8,006.799 N
- 1,825 lbf = 8,118.004 N
- 1,850 lbf = 8,229.21 N
- 1,875 lbf = 8,340.416 N
- 1,900 lbf = 8,451.621 N
- 1,925 lbf = 8,562.827 N
- 1,950 lbf = 8,674.032 N
- 1,975 lbf = 8,785.238 N
- 2,000 lbf = 8,896.443 N
- 2,050 lbf = 9,118.854 N
- 2,100 lbf = 9,341.265 N
- 2,150 lbf = 9,563.676 N
- 2,200 lbf = 9,786.088 N
- 2,250 lbf = 10,008.499 N
- 2,300 lbf = 10,230.91 N
- 2,350 lbf = 10,453.321 N
- 2,400 lbf = 10,675.732 N
- 2,450 lbf = 10,898.143 N
- 2,500 lbf = 11,120.554 N
- 2,550 lbf = 11,342.965 N
- 2,600 lbf = 11,565.376 N
- 2,650 lbf = 11,787.787 N
- 2,700 lbf = 12,010.198 N
- 2,750 lbf = 12,232.609 N
- 2,800 lbf = 12,455.021 N
- 2,850 lbf = 12,677.432 N
- 2,900 lbf = 12,899.843 N
- 2,950 lbf = 13,122.254 N
- 3,000 lbf = 13,344.665 N
- 3,050 lbf = 13,567.076 N
- 3,100 lbf = 13,789.487 N
- 3,150 lbf = 14,011.898 N
- 3,200 lbf = 14,234.309 N
- 3,250 lbf = 14,456.72 N
- 3,300 lbf = 14,679.131 N
- 3,350 lbf = 14,901.542 N
- 3,400 lbf = 15,123.953 N
- 3,450 lbf = 15,346.365 N
- 3,500 lbf = 15,568.776 N
- 3,550 lbf = 15,791.187 N
- 3,600 lbf = 16,013.598 N
- 3,650 lbf = 16,236.009 N
- 3,700 lbf = 16,458.42 N
- 3,750 lbf = 16,680.831 N
- 3,800 lbf = 16,903.242 N
- 3,850 lbf = 17,125.653 N
- 3,900 lbf = 17,348.064 N
- 3,950 lbf = 17,570.475 N
- 4,000 lbf = 17,792.886 N
- 4,050 lbf = 18,015.298 N
- 4,100 lbf = 18,237.709 N
- 4,150 lbf = 18,460.12 N
- 4,200 lbf = 18,682.531 N
- 4,250 lbf = 18,904.942 N
- 4,300 lbf = 19,127.353 N
- 4,350 lbf = 19,349.764 N
- 4,400 lbf = 19,572.175 N
- 4,450 lbf = 19,794.586 N
- 4,500 lbf = 20,016.997 N
- 4,550 lbf = 20,239.408 N
- 4,600 lbf = 20,461.819 N
- 4,650 lbf = 20,684.231 N
- 4,700 lbf = 20,906.642 N
- 4,750 lbf = 21,129.053 N
- 4,800 lbf = 21,351.464 N
- 4,850 lbf = 21,573.875 N
- 4,900 lbf = 21,796.286 N
- 4,950 lbf = 22,018.697 N
- 5,000 lbf = 22,241.108 N
- 5,100 lbf = 22,685.93 N
- 5,200 lbf = 23,130.752 N
- 5,300 lbf = 23,575.575 N
- 5,400 lbf = 24,020.397 N
- 5,500 lbf = 24,465.219 N
- 5,600 lbf = 24,910.041 N
- 5,700 lbf = 25,354.863 N
- 5,800 lbf = 25,799.685 N
- 5,900 lbf = 26,244.508 N
- 6,000 lbf = 26,689.33 N
- 6,100 lbf = 27,134.152 N
- 6,200 lbf = 27,578.974 N
- 6,300 lbf = 28,023.796 N
- 6,400 lbf = 28,468.618 N
- 6,500 lbf = 28,913.44 N
- 6,600 lbf = 29,358.263 N
- 6,700 lbf = 29,803.085 N
- 6,800 lbf = 30,247.907 N
- 6,900 lbf = 30,692.729 N
- 7,000 lbf = 31,137.551 N
- 7,100 lbf = 31,582.373 N
- 7,200 lbf = 32,027.196 N
- 7,300 lbf = 32,472.018 N
- 7,400 lbf = 32,916.84 N
- 7,500 lbf = 33,361.662 N
- 7,600 lbf = 33,806.484 N
- 7,700 lbf = 34,251.306 N
- 7,800 lbf = 34,696.129 N
- 7,900 lbf = 35,140.951 N
- 8,000 lbf = 35,585.773 N
- 8,100 lbf = 36,030.595 N
- 8,200 lbf = 36,475.417 N
- 8,300 lbf = 36,920.239 N
- 8,400 lbf = 37,365.062 N
- 8,500 lbf = 37,809.884 N
- 8,600 lbf = 38,254.706 N
- 8,700 lbf = 38,699.528 N
- 8,800 lbf = 39,144.35 N
- 8,900 lbf = 39,589.172 N
- 9,000 lbf = 40,033.995 N
- 9,100 lbf = 40,478.817 N
- 9,200 lbf = 40,923.639 N
- 9,300 lbf = 41,368.461 N
- 9,400 lbf = 41,813.283 N
- 9,500 lbf = 42,258.105 N
- 9,600 lbf = 42,702.928 N
- 9,700 lbf = 43,147.75 N
- 9,800 lbf = 43,592.572 N
- 9,900 lbf = 44,037.394 N
- 10,000 lbf = 44,482.216 N
The factor comes from two exact definitions, the pound at 0.45359237 kilogram and standard gravity at 9.80665 meters per second squared, fixed by the 3rd General Conference on Weights and Measures in 1901. Their product is 4.4482216152605 newtons, with no rounding. Methodology & sources.
Frequently asked questions
What is the difference between lb and lbf?
The pound is a mass, the pound-force is the weight of that mass under standard gravity. One pound is exactly 0.45359237 kilogram and one pound-force is exactly 4.4482216152605 newtons. American datasheets often write lb for both, sometimes lbm for the mass and lbf for the force, and only the surrounding sentence tells you which is meant.
What are the slug and the poundal?
Two ways of making mechanics consistent while counting in feet and pounds. The slug is the mass that one pound-force accelerates at one foot per second squared: it weighs 14.5939 kilograms, or 32.174 pounds. The poundal does the opposite, it is the force that accelerates one pound at one foot per second squared, and it is only 0.1383 newton. American engineering often keeps the pound on both sides instead and carries a constant, written gc, equal to 32.174.
What does a sling rated 4,000 lb actually hold?
That figure is a working load limit, not a breaking strength. American lifting gear carries its WLL in pounds and ASME B30.9 requires a design factor of 5 for a synthetic web sling: failure therefore comes near 20,000 pounds, or 89 kilonewtons. The European standard EN 1492 uses a factor of 7 and prints the same information in kilograms, so two labels cannot be compared without converting the factor as well.
Does a magnet rated at 50 pounds really hold 50 pounds?
Rarely. The quoted pull force, 50 pounds or 222 newtons, is measured under ideal conditions: direct contact with no paint or gap, a thick mild steel plate, and a pull perpendicular to the surface. Thin sheet metal, a coat of paint or a peeling angle cut the figure by half or more, and resistance to sideways sliding is only a fraction of the rated pull.
How are forces smaller than a pound written?
In ounces-force, grams-force or centinewtons. One ounce-force is 0.2780 newton and one gram-force is 0.00980665 newton. This is the language of small mechanisms: a mechanical keyboard switch is specified at 45 grams-force, that is 0.44 newton or 1.6 ounce-force, and the same units serve springs, microswitches and peel tests.