Gram to Pound Converter

The exact definition behind the conversion

Since 1959 the United States, the United Kingdom, Canada, Australia, New Zealand and South Africa have shared one definition of the pound: exactly 0.45359237 kg, which is 453.59237 grams. The word exact matters. This is not a measured average or a rounded constant, it is the definition, agreed at the international yard and pound conference and printed in NIST Special Publication 811 (2008 edition), the federal guide to using SI units. Because the factor is exact, a conversion done today matches one done fifty years ago to the last decimal.

Everything else on this page follows from that single number. The ounce is one sixteenth of the pound, so it is exactly 28.349523125 g. The kilogram is 1000 g by SI definition, the system maintained by the BIPM SI Brochure (9th edition, 2019, updated 2026), so one kilogram is 1000 / 453.59237 = 2.2046226 lb. NIST's package labeling conversion chart (SP 1020-1) prints the same factors in the form inspectors use.

Rounding is the only place judgment enters. The converter computes with the full exact factors and displays three decimals, which is finer than any kitchen scale reads and finer than postage steps.

Grams to pounds, worked examples

The formula is one division: pounds = grams / 453.59237. For 500 g of flour, 500 / 453.59237 = 1.102 lb. The same 500 g is 0.5 kg, and in ounces 500 / 28.349523125 = 17.637 oz. A recipe that calls for a pound of flour is asking for 453.59 g, so a 500 g purchase runs about 46 g heavy.

Each row is the widget's own output for that input: enter 250, choose grams, and the tool prints 0.551 lb and 8.818 oz. The half-pound line is worth a second look, because 250 g sits 23.2 g above a true half pound, which is 226.80 g.

Pounds to grams, worked examples

The reverse direction is one multiplication: grams = pounds x 453.59237. For 2 lb of flour, 2 x 453.59237 = 907.18 g. For a 5 lb bag of sugar, 5 x 453.59237 = 2267.96 g, which is why metric-label bags sold abroad cluster near 2.27 kg.

Fractional pounds are where the exact factor pays off. A recipe written for 1.5 lb of potatoes needs 680.39 g, and a 2.25 lb chicken is 1020.58 g, so a scale set to grams can follow either recipe without a conversion chart. Rounding to the nearest 5 g in the kitchen keeps the error under half a percent of the weight.

The ounce column multiplies the pound by 16, which is exact by definition, so 8 oz is exactly 226.796 g and the widget shows 226.80. Enter 2, choose pounds, and the tool prints 907.18 g and 32.000 oz, matching the table row for row.

Grams, ounces and kilograms together

Four factors cover the whole family, and each one is exact: 1 lb = 453.59237 g, 1 oz = 28.349523125 g, 1 kg = 1000 g, and 16 oz = 1 lb. From those, 1 kg = 2.205 lb to three decimals (2.2046226 before rounding), and 1 g = 0.002205 lb = 0.035274 oz.

The gram row shows why the display widens to six decimals for small results: at three decimals a gram would round to 0.000 lb and hide the answer. The stone row is 14 lb, the British body-weight unit, included because UK recipes mix it with grams freely.

Kitchen references you can weigh by eye

Numbers stick when they attach to objects. A US stick of butter is a quarter pound, exactly 113.3980925 g, so 113.4 g on a scale reads 0.250 lb and 4.000 oz. Four sticks are the 453.59 g pound, which is why American butter wrappers print tablespoon marks: the package is a mass standard you already own.

The egg, flour and sugar cup figures are food-industry conventions and vary with how firmly you pack a cup, so treat them as anchors with slop, not constants. The butter stick and the 5 lb bag are definitions and print exact. An 85 g patty reads 2.998 oz, the size US packages call a third of a pound, so the 85 g figure stands in for 3 oz rather than for a quarter pound, which is 113.4 g.

The 454 shortcut and when it is safe

Most people carry 454 as the mental pound. It is a good constant with a known error: 454 - 453.59237 = 0.41 g, about 0.09 percent. Run 454 g through the converter and it reads 1.001 lb, four tenths of a gram over one true pound. For recipes, luggage estimates and grocery comparisons, the shortcut is fine.

Check the 454 row by hand: 500 / 454 = 1.101 lb against the tool's 1.102, a slip of one part in a thousand. The 450 row is where errors start to show: 1.111 lb is off by 0.009 lb, about 4 g. Use the shortcut to sanity-check a number, then let the exact factor give the digits you write down.

Troy ounces, fluid ounces and other traps

Not every ounce is the ounce above. Precious metals trade in troy ounces, exactly 31.1034768 g per NIST Handbook 44, Appendix C (2026 edition). That is about 9.7 percent heavier than the 28.349523125 g avoirdupois ounce, so a troy ounce of silver outweighs a kitchen ounce of the same metal. If a calculator multiplies by 31.1 when you expected 28.35, you are in the wrong ounce.

Fluid ounces are a different unit altogether: they measure volume, not mass. A fluid ounce of water weighs about 29.6 g, close to but not equal to a weight ounce, and a fluid ounce of flour weighs far less because flour is mostly air. Converting milliliters to grams needs the density of the ingredient, never this page.

One more trap: package net weight is the food, not the container, and serving sizes on US labels may be printed in grams while the front of the box says ounces. The two figures on the same bag can disagree by rounding; the gram figure is the one the label math uses.

How to use this converter

Type a weight, pick the unit it is in from the dropdown, and the tool fills all four fields: grams, kilograms, pounds and ounces. The math uses the exact factors, 453.59237 g per pound and 28.349523125 g per ounce, and the display rounds to three decimals, widening to six decimals for small results.

Everything runs in your browser, and nothing you type is uploaded or stored. For a quick start, try 500 g to see 1.102 lb, then switch the unit to pounds and enter 2 to see 907.18 g come back. The related pages below handle price per pound and the other common weight pairs if you need a different direction.