Weight Converter

How do I convert kilograms to pounds, ounces and stones quickly?

Use this free online weight converter: type a value, pick the unit you have and the unit you want, then press the Convert button. The tool handles kilograms, grams, milligrams, metric tonnes, pounds, ounces and stones, and the answer appears on the page in under a second with up to six decimal places.

What does the weight converter do and why is it useful?

Weight is measured in very different systems around the world. Recipes from the United States use ounces and pounds, a British bathroom scale may show stones, a shipping label may list tonnes, and a laboratory sheet is written in milligrams. Moving between them by hand means remembering several awkward factors, and one slipped digit can ruin a recipe, a parcel quote or a dosage note.

This converter removes that friction. You enter one number, choose a source unit and a target unit, and the result is shown straight away after you press the button. It covers seven units: kilograms, grams, milligrams, tonnes (metric), pounds, ounces and stones. If you also work with distances, the length unit converter follows the same simple pattern.

How does the converter work under the hood?

Every conversion passes through one common base unit, the kilogram. The value you type is first multiplied by the number of kilograms in the source unit. That figure is then divided by the number of kilograms in the target unit. Using a single base keeps the maths consistent and means any unit can be converted to any other without a separate table for each pair.

The factors are the standard international definitions:

• 1 pound = 0.45359237 kilograms, an exact value.
• 1 ounce = 28.349523125 grams, also exact (one sixteenth of a pound).
• 1 stone = 6.35029318 kilograms, which is 14 pounds.
• 1 metric tonne = 1000 kilograms.
• 1 kilogram = 1000 grams, and 1 gram = 1000 milligrams.

The result is rounded to a maximum of six decimal places. Nothing updates while you type. The calculation runs only when you press Convert, so you can change the value or either unit freely and the displayed answer stays put until you ask for a new one.

How do I use the weight converter step by step?

1. Type the number you want to convert into the value field.
2. Choose the unit you are starting from in the first drop-down list.
3. Choose the unit you want to end up with in the second drop-down list.
4. Press the Convert button.
5. Read the result shown on the page. To try another value or another pair of units, change the fields and press Convert again.

What do real conversions look like? Worked examples

Each figure below was calculated from the exact factors listed above, so you can use them to check the tool yourself.

Example 1: 70 kilograms to pounds

Input: 70, from kilograms, to pounds. Calculation: 70 / 0.45359237. Result: 154.323584 lb.

Example 2: 160 pounds to kilograms

Input: 160, from pounds, to kilograms. Calculation: 160 x 0.45359237. Result: 72.574779 kg.

Example 3: 8 ounces to grams

Input: 8, from ounces, to grams. Calculation: 8 x 28.349523125. Result: 226.796185 g. This is half a pound, which matches the common baking figure of roughly 227 grams for a stick of butter.

Example 4: 12 stone to kilograms and pounds

Input: 12, from stones, to kilograms. Calculation: 12 x 6.35029318. Result: 76.203518 kg. Switching the target to pounds gives 168 lb, since 12 x 14 = 168.

Example 5: 500 grams to ounces

Input: 500, from grams, to ounces. Calculation: 500 / 28.349523125. Result: 17.636981 oz.

Example 6: 2.5 tonnes to kilograms

Input: 2.5, from tonnes (metric), to kilograms. Calculation: 2.5 x 1000. Result: 2500 kg. Choosing grams as the target instead returns 2,500,000 g.

How do the seven units compare at a glance?

Unit	Equal to
1 tonne (metric)	1000 kg
1 kilogram	1000 g
1 gram	1000 mg
1 stone	6.35029318 kg (14 lb)
1 pound	0.45359237 kg (16 oz)
1 ounce	28.349523125 g

Keep this table in mind when you estimate in your head. A kilogram is a little more than two pounds, a stone is a little more than six kilograms, and an ounce is close to twenty-eight grams. The tool does the exact work, and these rough anchors help you notice a typing error before it matters.

What tips help me get accurate results?

• Use the base-unit idea as a sanity check: a pound is a little under half a kilogram, so 160 lb should land a bit under 80 kg, and it does.
• Keep the full precision while you work and round only the final figure for display or printing.
• For recipes, convert the whole amount in one step instead of chaining several conversions, which can pile up rounding differences.
• When a number looks wrong, check that the from and to units are not swapped. This is the most frequent cause of surprising answers.
• For tiny quantities, such as medicine or lab samples, convert into milligrams or grams to avoid a long string of leading zeros.
• Combine this tool with the BMI calculator when a health form asks for kilograms and your scale shows pounds.

What common mistakes should I avoid?

• Mixing up ounces of weight with fluid ounces. This tool converts weight only. Fluid ounces measure volume, so use the volume converter for liquids.
• Confusing tonnes with tons. The tool uses the metric tonne, which is 1000 kilograms. A US short ton or a UK long ton is a different quantity and is not included.
• Treating a stone as a decimal unit. A stone is 14 pounds, not 10. Writing 11 stone 7 pounds means 11 stone plus 7 pounds, so convert each part or turn the total into pounds first.
• Forgetting that the result is rounded. Six decimals is plenty for daily use, but a very small number may need a smaller unit to show meaningful digits.
• Expecting the result to change as you type. It updates only after you press Convert.

Who uses a weight converter?

Home cooks translate foreign recipes. Travellers check airline baggage limits quoted in kilograms against a scale showing pounds. Online sellers fill in shipping forms that ask for grams or ounces. Fitness enthusiasts compare barbell plates in pounds with a gym log in kilograms. Students use it for science and maths homework, and small manufacturers convert between tonnes, kilograms and grams when ordering materials. Anyone who reads products from more than one country meets these units sooner or later.

Is my data private?

Yes. The calculation runs entirely in your browser, so the numbers you enter are never uploaded to a server or stored. Closing or refreshing the page clears everything. There is no account, no history and no saved list of earlier conversions.

What are the limitations of this tool?

• It supports exactly seven units: kilograms, grams, milligrams, metric tonnes, pounds, ounces and stones. Troy ounces, carats, US tons and other units are not offered.
• Results show at most six decimal places.
• It converts one value at a time. There is no batch mode, and no copy button or file download.
• It does not measure anything. It only does arithmetic on the number you provide, so the answer is only as good as the input.

Frequently asked questions

How many pounds are in a kilogram?

One kilogram is about 2.204623 pounds. The converter gets this by dividing 1 by 0.45359237.

How many grams are in an ounce?

One ounce is 28.349523125 grams, an exact definition, shown rounded to six decimals in results.

How many pounds are in a stone?

Fourteen. One stone equals 14 pounds, or 6.35029318 kilograms.

Is a tonne the same as a ton?

No. The tool uses the metric tonne, equal to 1000 kilograms. The word ton can refer to other, different units depending on the country.

Why is the answer not a round number?

The pound is defined as exactly 0.45359237 kilograms, so most conversions between the metric and imperial systems produce long decimals. Only a few pairs, such as 12 stone to 168 pounds, come out clean.

Can I convert between two imperial units, such as stones to ounces?

Yes. Any of the seven units can be paired with any other, imperial to imperial included.

Does it need an internet connection after loading?

The arithmetic happens locally in the page, so nothing is sent anywhere when you press Convert.

Where can I find more utilities?

Browse the full set of free tools on the hub page.

Convert weights with confidence

A single value, two unit choices and one press of the Convert button are all it takes to move between kilograms, pounds, ounces, stones, tonnes, grams and milligrams. Use the worked examples above to confirm the results, keep the units straight, and round only at the end.