Convert Troy ounces to Milligrams
1 troy ounce is 31,103.48 mg. One troy ounce is exactly 31103.4768 milligrams.
One troy ounce is 31103.477 milligrams. To convert troy ounces to milligrams, multiply by 31103.477; to go the other way, divide by 31103.477 or multiply by 3.2151 × 10^-5. 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 × 31103.477
1 * 31103.47731,103.477 mg
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 milligrams? The converter and the working
- 1.Take the measurement in troy ounces.
- 2.Multiply by 31103.477 — that is how many milligrams fit in one troy ounce.
- 3.To go back the other way, divide by 31103.477, or multiply by 3.2151 × 10^-5.
Worked example: 25 troy ounces to milligrams
- Formula
- ozt × 31103.477 = mg
- Arithmetic
- 25 × 31103.477 = 777,586.92 mg
- Answer
- 25 ozt = 777,586.92 mg
The factor is rounded for display; the figure above is computed from the full value.
Troy ounces to milligrams conversion table
| Troy ounces | Milligrams |
|---|---|
| 1 ozt | 31,103.48 mg |
| 2 ozt | 62,206.95 mg |
| 3 ozt | 93,310.43 mg |
| 4 ozt | 124,413.91 mg |
| 5 ozt | 155,517.38 mg |
| 6 ozt | 186,620.86 mg |
| 7 ozt | 217,724.34 mg |
| 8 ozt | 248,827.81 mg |
| 9 ozt | 279,931.29 mg |
| 10 ozt | 311,034.77 mg |
| 12 ozt | 373,241.72 mg |
| 15 ozt | 466,552.15 mg |
| 20 ozt | 622,069.54 mg |
| 25 ozt | 777,586.92 mg |
| 50 ozt | 1,555,173.84 mg |
| 100 ozt | 3,110,347.68 mg |
| 200 ozt | 6,220,695.36 mg |
| 300 ozt | 9,331,043.04 mg |
| 500 ozt | 15,551,738.4 mg |
| 1000 ozt | 31,103,476.8 mg |
| 2000 ozt | 62,206,953.6 mg |
| 5000 ozt | 155,517,384 mg |
| 10000 ozt | 311,034,768 mg |
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 milligram?
One thousandth of a gram, and exactly 1,000 micrograms. The unit almost every medicine is dosed in.
How many milligrams are in a troy ounce?
One troy ounce is 31103.477 milligrams. Going the other way, one milligram is 3.2151 × 10^-5 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 milligrams. Rule Calculator. https://rulecalculators.com/convert/troy-ounce-to-milligram
- MLA
- "Convert Troy ounces to milligrams." Rule Calculator, August 16, 2026, https://rulecalculators.com/convert/troy-ounce-to-milligram.
- Chicago
- Rule Calculator. "Convert Troy ounces to milligrams." Rule Calculator. Last reviewed August 16, 2026. https://rulecalculators.com/convert/troy-ounce-to-milligram.
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Questions people actually ask
- How many milligrams are in a troy ounce?
- 31103.477. One thousandth of a gram, and exactly 1,000 micrograms. The unit almost every medicine is dosed in.
- How do I convert milligrams back to troy ounces?
- Divide by 31103.477, or multiply by 3.2151 × 10^-5 — they are the same operation.
Other weight conversions
Milligrams to troy ounces — the same conversion the other way.