Cookies for analytics and advertising
We use cookies for analytics and advertising, both sent to Google. Refusing changes nothing you can see.Read the privacy page
Convert lb to t
1 lb = 0.00045359237 t
Type a value in pounds and the answer in tonnes appears as you go. The conversion is exactly 0.00045359237 t to the pound, and it happens on your own machine — this page asks nothing of a server once it has loaded.
Where it runs
In your browser. The number you type is never part of a request.
Exact by definition
1 lb is exactly 0.00045359237 t — a definition, not a rounded factor.
Answers as you type
No button, no wait. The worked answer is already on the page before any script runs.
Pound and Tonne
A pound is exactly 0.45359237 kilograms by the same 1959 agreement that fixed the inch. The abbreviation "lb" comes from libra, the Roman unit it descends from.
A tonne is 1,000 kilograms, and it is not the same as either the US short ton (907 kg) or the UK long ton (1,016 kg). Where the difference matters, this one is sometimes written "metric ton".
pounds to tonnes in practice
50 lb is 0.02268 t
— a US bag of cement.
20 lb is 0.009072 t
— a large sack of dog food.
pounds to tonnes at a glance
| lb | t |
|---|---|
| 1 | 0.00045359237 |
| 2 | 0.00090718474 |
| 3 | 0.00136077711 |
| 5 | 0.00226796185 |
| 10 | 0.0045359237 |
| 20 | 0.0090718474 |
| 50 | 0.0226796185 |
| 100 | 0.045359237 |
Every figure here is computed from the same definition the calculator uses, so the table cannot drift away from the answer above it.
Convert lb to t: common questions
How many tonnes are in a pound?
Exactly 0.00045359237. One pound is 0.00045359237 tonnes, and the box above will do it for any figure you type.
Is this conversion exact, or rounded?
The ratio is exact. It is not a rounded constant typed into a table: it is derived from the definitions of the two units, so it agrees with any other correct converter to as many digits as you care to compare.
Why does another converter show a slightly different number?
Almost always rounding rather than disagreement. Many converters cut the answer to two or four decimals, and some carry a factor that was rounded before the multiplication rather than after. The figures here are computed from the exact definitions and only rounded on the way to the screen.
Where these figures come from
The claims this page makes about weight units are checkable, and these are the documents that settle them.
How this page works
The factor is a constant in the page and the arithmetic is four operations, so nothing is sent anywhere and nothing needs to be. The number you type never leaves the browser — there is no request for it to travel in.