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Convert oz to t
1 oz = 0.000028349523125 t
Type a value in ounces and the answer in tonnes appears as you go. The conversion is exactly 0.000028349523125 t to the ounce, 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 oz is exactly 0.000028349523125 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.
Ounce and Tonne
An ounce is a sixteenth of a pound. It is not the fluid ounce, which measures volume, and the two are only loosely related — a fluid ounce of water weighs about an ounce, which is where the name came from and where the confusion starts.
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".
ounces to tonnes in practice
16 oz is 0.0004536 t
— a pound of flour.
8 oz is 0.0002268 t
— half a pound.
ounces to tonnes at a glance
| oz | t |
|---|---|
| 1 | 0.000028349523125 |
| 2 | 0.00005669904625 |
| 3 | 0.000085048569375 |
| 5 | 0.000141747615625 |
| 10 | 0.00028349523125 |
| 20 | 0.0005669904625 |
| 50 | 0.00141747615625 |
| 100 | 0.0028349523125 |
Every figure here is computed from the same definition the calculator uses, so the table cannot drift away from the answer above it.
Convert oz to t: common questions
How many tonnes are in a ounce?
Exactly 0.000028349523125. One ounce is 0.000028349523125 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.