Convert Troy ounces to Tonnes
1 troy ounce is 0.0000311 t. One troy ounce is exactly 0.0000311034768 tonnes.
One troy ounce is 3.1103 × 10^-5 tonnes. To convert troy ounces to tonnes, multiply by 3.1103 × 10^-5; to go the other way, divide by 3.1103 × 10^-5 or multiply by 32150.747. 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. Exactly 31.1034768 grams, and the only ounce bullion is ever quoted in.
Factor checked against the defining standard · How we check
- Troy ounces × 3.1103 × 10^-5
1 * 0.00003110 t
1 troy ounce in every weight unit
| Unit | Value | Exact factor |
|---|---|---|
| ounces | 1.097142857 oz | × 1.09714285714 |
| pounds | 0.06857142857 lb | × 0.0685714285714 |
| stone | 0.004897959184 st | × 0.00489795918367 |
| US tons | 0.00003428571429 ton | × 0.0000342857142857 |
| micrograms | 31,103,476.8 mcg | × 31,103,476.8 |
| milligrams | 31,103.4768 mg | × 31,103.4768 |
| centigrams | 3,110.34768 cg | × 3,110.34768 |
| grams | 31.1034768 g | × 31.1034768 |
| kilograms | 0.0311034768 kg | × 0.0311034768 |
| slugs | 0.002131265155 slug | × 0.00213126515462 |
| tonnes | 0.0000311034768 t | × 0.0000311034768 |
| carats | 155.517384 ct | × 155.517384 |
| troy ounces (as entered) | 1 ozt | — |
| grains | 480 gr | × 480 |
| long tons | 0.0000306122449 LT | × 0.000030612244898 |
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 troy ounces to tonnes? The converter and the working
- 1.Take the measurement in troy ounces.
- 2.Multiply by 3.1103 × 10^-5 — that is how many tonnes fit in one troy ounce.
- 3.To go back the other way, divide by 3.1103 × 10^-5, or multiply by 32150.747.
Worked example: 25 troy ounces to tonnes
- Formula
- ozt × 3.1103 × 10^-5 = t
- Arithmetic
- 25 × 3.1103 × 10^-5 = 0.0007776 t
- Answer
- 25 ozt = 0.0007776 t
The factor is rounded for display; the figure above is computed from the full value.
Troy ounces to tonnes conversion table
| Troy ounces | Tonnes |
|---|---|
| 1 ozt | 0.0000311 t |
| 2 ozt | 0.00006221 t |
| 3 ozt | 0.00009331 t |
| 4 ozt | 0.0001244 t |
| 5 ozt | 0.0001555 t |
| 6 ozt | 0.0001866 t |
| 7 ozt | 0.0002177 t |
| 8 ozt | 0.0002488 t |
| 9 ozt | 0.0002799 t |
| 10 ozt | 0.000311 t |
| 12 ozt | 0.0003732 t |
| 15 ozt | 0.0004666 t |
| 20 ozt | 0.0006221 t |
| 25 ozt | 0.0007776 t |
| 50 ozt | 0.001555 t |
| 100 ozt | 0.00311 t |
| 200 ozt | 0.01 t |
| 300 ozt | 0.01 t |
| 500 ozt | 0.02 t |
| 1000 ozt | 0.03 t |
| 2000 ozt | 0.06 t |
| 5000 ozt | 0.16 t |
| 10000 ozt | 0.31 t |
What is a troy ounce?
Exactly 31.1034768 grams, and the only ounce bullion is ever quoted in. It is about 10% heavier than the ounce on a kitchen scale, so a "pound" of gold — twelve troy ounces — is lighter than a pound of anything else.
What is a tonne?
One thousand kilograms, also called the metric ton — 2,204.6 pounds.
How many tonnes are in a troy ounce?
One troy ounce is 3.1103 × 10^-5 tonnes. Going the other way, one tonne is 32150.747 troy 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 a troy ounce.
Cite this page
- APA
- Rule Calculator. (2026). Convert Troy ounces to tonnes. Rule Calculator. https://rulecalculators.com/convert/troy-ounce-to-tonne
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- Chicago
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Questions people actually ask
- How many tonnes are in a troy ounce?
- 3.1103 × 10^-5. One thousand kilograms, also called the metric ton — 2,204.6 pounds.
- How do I convert tonnes back to troy ounces?
- Divide by 3.1103 × 10^-5, or multiply by 32150.747 — they are the same operation.
Other weight conversions
Tonnes to troy ounces — the same conversion the other way.