Compare scale readings and product weights
This converter handles the mass units commonly printed on packages and shown on household, shipping, luggage, kitchen, and body-weight scales. In everyday language these are called weight units, although kilograms and grams technically measure mass.
Use the number exactly as shown with its source unit. Pay particular attention to ounces and fluid ounces: ounces here mean mass. A fluid ounce measures volume and cannot be converted to grams without knowing the substance and its density.
Weight conversion factors
The calculator uses grams as a shared base and the international avoirdupois definitions used for ordinary goods and body weight.
1 kilogram = 1,000 grams.
1 international avoirdupois pound = 453.59237 grams exactly.
1 avoirdupois ounce = 1/16 pound = 28.349523125 grams.
1 stone = 14 pounds = 6.35029318 kilograms.
Destination value = source value × source mass in grams ÷ destination mass in grams.
Conversions in real situations
Convert a 23-kilogram baggage allowance to pounds.
23 kg = 50.71 poundsAirlines enforce their published unit and scale reading, so treat the conversion as a guide rather than a reason to pack to the exact boundary.
Convert 8 ounces of flour by weight to grams.
8 oz = 226.8 gramsThis is a mass conversion. It does not apply to 8 US fluid ounces measured in a cup.
Convert 12 stone to pounds.
12 st = 168 poundsMultiply stones by 14. The pound result can then be converted to kilograms if needed.
Mass, weight, and context
For normal Earth-based labels and scales, direct conversion between these units is appropriate. Scientific force calculations are different: weight force depends on local gravitational acceleration and is measured in newtons, not kilograms or pounds-mass.
Shipping carriers may charge by dimensional weight rather than scale weight. This converter changes the unit of a measured mass only; it does not calculate billable weight, packaging allowances, or carrier rounding bands.
What this conversion does not decide
- Fluid ounces are not included because they measure volume rather than mass.
- Troy ounces, used for precious metals, differ from the avoirdupois ounces used here.
- The converter does not calculate density, dimensional shipping weight, or gravitational force.
- Scale accuracy and product-label rounding limit the meaningful precision of the result.
Weight & mass questions
How many pounds are in a kilogram?
One kilogram is approximately 2.20462 international avoirdupois pounds.
Are ounces the same as fluid ounces?
No. Ounces on this page measure mass. Fluid ounces measure volume, and converting them to grams requires the density of the ingredient or liquid.
How many pounds are in a stone?
One stone equals exactly 14 international avoirdupois pounds.
Can I convert precious-metal ounces here?
No. Gold and other precious metals commonly use troy ounces, which are heavier than the avoirdupois ounces used for ordinary goods.
Does this calculate shipping weight?
It converts an existing scale weight between units. Carrier billable weight may instead use package dimensions, minimums, and carrier-specific rounding rules.