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Weight Converter
Convert kg, pounds, ounces, stone and grams.
100% FreeRuns instantlyNo watermark
- 1Enter detailsAdd the numbers for your scenario.
- 2CalculateVootkit updates the result instantly.
- 3ReviewCheck totals, notes and breakdowns.
Private by designProcessed on your device where possible.
Works on any deviceDesktop, tablet and mobile browsers.
No installationOpen the page and start working.
Always free coreUse the free plan for everyday tasks.
How to use Weight Converter
Vootkit updates the result instantly.
02Check totals, notes and breakdowns.
03Copy the answer into your workflow.
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Your work is processed locally in your browser where possible and is never added to a Vootkit upload library.
Learn more about privacyRecipes, freight documents and bathroom scales all use different units for the same quantity, and the one that trips people up is the stone — a unit of 14 pounds that is still in everyday use in Britain and Ireland and almost nowhere else.
What Weight Converter does
Converts between metric and imperial mass units using exact factors. A pound is exactly 0.45359237 kg, defined by the same 1959 agreement that fixed the inch.
Includes stone at 6.35029318 kg — exactly 14 pounds. Software written outside the UK routinely omits it, which is why British body-weight figures so often need converting by hand.
Exact factors, in kilograms
| Tonne | 1000 — metric tonne, not a US ton |
|---|---|
| Pound | 0.45359237 — exact by definition |
| Ounce | 0.0283495231 |
| Stone | 6.35029318 — exactly 14 pounds |
| Gram | 0.001 |
| Milligram | 0.000001 |
| Default conversion | Pounds → kilograms |
| Strictly | These are units of MASS, not weight |
Detailed steps
- Enter the value.
- Choose the unit you have and the one you want.
- Read the result alongside every other unit.
Worth knowing
Watch which ton you mean. A metric tonne is 1000 kg, a US short ton is about 907 kg, and a UK long ton about 1016 kg — a spread of over 10%. Freight paperwork that says "ton" without qualifying it is ambiguous, and the difference is real money on a shipping invoice.
Frequently Asked Questions
How many pounds in a stone?
Exactly 14, which is 6.35029318 kg. It survives in everyday use in Britain and Ireland for body weight and almost nowhere else, so most software omits it entirely.
Is a tonne the same as a ton?
No, and this catches people out. A tonne is metric, 1000 kg. A US short ton is 2000 lb, about 907 kg; a UK long ton is 2240 lb, about 1016 kg. Only the metric tonne is listed here, to avoid the ambiguity.
Mass or weight — does the distinction matter?
Technically these are mass units; weight is a force and varies with gravity. In everyday use the two are treated as interchangeable on Earth, and only physics and some engineering contexts need to care.
Why is a pound such an odd number of kilograms?
Because 0.45359237 was chosen in 1959 to reconcile slightly different existing US and UK pounds. It is exact by definition rather than derived — the awkwardness is the price of making both countries agree.
Is Weight Converter free?
Yes. The Vootkit free plan includes 5 tool runs a day. Upgrade to Vootkit Pro for unlimited daily use, an ad-free workspace and saved workflows.
Are my files uploaded?
No. Weight Converter runs entirely in your browser — your file is processed on your own device and never sent to a server. There is nothing for us to store or delete.
Do I need to install anything?
No. Weight Converter works in any modern browser on desktop, tablet or phone. Open the page and start.
How often can I use it? Is there a daily limit?
On the free plan you get 5 tool runs a day. When you reach the limit you'll see a prompt to upgrade, and it resets the next day. Vootkit Pro removes the cap entirely for unlimited daily use.
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