Convert Ounces to Tonnes
1 ounce is 0.00002835 t. One ounce is exactly 0.000028349523125 tonnes.
One ounce is 2.8350 × 10^-5 tonnes. To convert ounces to tonnes, multiply by 2.8350 × 10^-5; to go the other way, divide by 2.8350 × 10^-5 or multiply by 35273.962. The relation is exact but the figure is not: it is a rounding of a number that does not terminate, and it follows from NIST Handbook 44. One sixteenth of a pound.
Factor checked against the defining standard · How we check
- Ounces × 2.8350 × 10^-5
1 * 0.00002830 t
1 ounce in every weight unit
| Unit | Value | Exact factor |
|---|---|---|
| ounces (as entered) | 1 oz | — |
| pounds | 0.0625 lb | × 0.0625 |
| stone | 0.004464285714 st | × 0.00446428571429 |
| US tons | 0.00003125 ton | × 0.00003125 |
| micrograms | 28,349,523.13 mcg | × 28,349,523.125 |
| milligrams | 28,349.52313 mg | × 28,349.523125 |
| centigrams | 2,834.952313 cg | × 2,834.9523125 |
| grams | 28.34952313 g | × 28.349523125 |
| kilograms | 0.02834952313 kg | × 0.028349523125 |
| slugs | 0.001942559386 slug | × 0.00194255938572 |
| tonnes | 0.00002834952313 t | × 0.000028349523125 |
| carats | 141.7476156 ct | × 141.747615625 |
| troy ounces | 0.9114583333 ozt | × 0.911458333333 |
| grains | 437.5 gr | × 437.5 |
| long tons | 0.00002790178571 LT | × 0.0000279017857143 |
Factors are entered by hand from NIST Handbook 44 rather than derived from a units library, so the ones that terminate are exact rather than rounded.
How do you convert ounces to tonnes? The converter and the working
- 1.Take the measurement in ounces.
- 2.Multiply by 2.8350 × 10^-5 — that is how many tonnes fit in one ounce.
- 3.To go back the other way, divide by 2.8350 × 10^-5, or multiply by 35273.962.
Worked example: 25 ounces to tonnes
- Formula
- oz × 2.8350 × 10^-5 = t
- Arithmetic
- 25 × 2.8350 × 10^-5 = 0.0007087 t
- Answer
- 25 oz = 0.0007087 t
The factor is rounded for display; the figure above is computed from the full value.
Ounces to tonnes conversion table
| Ounces | Tonnes |
|---|---|
| 1 oz | 0.00002835 t |
| 2 oz | 0.0000567 t |
| 3 oz | 0.00008505 t |
| 4 oz | 0.0001134 t |
| 5 oz | 0.0001417 t |
| 6 oz | 0.0001701 t |
| 7 oz | 0.0001984 t |
| 8 oz | 0.0002268 t |
| 9 oz | 0.0002551 t |
| 10 oz | 0.0002835 t |
| 12 oz | 0.0003402 t |
| 15 oz | 0.0004252 t |
| 20 oz | 0.000567 t |
| 25 oz | 0.0007087 t |
| 50 oz | 0.001417 t |
| 100 oz | 0.002835 t |
| 200 oz | 0.01 t |
| 300 oz | 0.01 t |
| 500 oz | 0.01 t |
| 1000 oz | 0.03 t |
| 2000 oz | 0.06 t |
| 5000 oz | 0.14 t |
| 10000 oz | 0.28 t |
What is an ounce?
One sixteenth of a pound. Not to be confused with the fluid ounce, which measures volume.
What is a tonne?
One thousand kilograms, also called the metric ton — 2,204.6 pounds.
How many tonnes are in an ounce?
One ounce is 2.8350 × 10^-5 tonnes. Going the other way, one tonne is 35273.962 ounces. Both figures come from the same defined relation rather than from a measurement, which is why they are the same today as they were in 1959.
Every weight unit here
The whole group — 15 units with their symbols and the size of each one in kilograms — is on the conversion index, along with every pair it makes. The table above already gives each of them relative to an ounce.
Cite this page
- APA
- Rule Calculator. (2026). Convert Ounces to tonnes. Rule Calculator. https://rulecalculators.com/convert/ounce-to-tonne
- MLA
- "Convert Ounces to tonnes." Rule Calculator, August 16, 2026, https://rulecalculators.com/convert/ounce-to-tonne.
- Chicago
- Rule Calculator. "Convert Ounces to tonnes." Rule Calculator. Last reviewed August 16, 2026. https://rulecalculators.com/convert/ounce-to-tonne.
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Questions people actually ask
- How many tonnes are in an ounce?
- 2.8350 × 10^-5. One thousand kilograms, also called the metric ton — 2,204.6 pounds.
- How do I convert tonnes back to ounces?
- Divide by 2.8350 × 10^-5, or multiply by 35273.962 — they are the same operation.
Other weight conversions
Tonnes to ounces — the same conversion the other way.