Convert Ounces to Milligrams
One ounce equals 28,349.52 milligrams. Type any value to convert ounces to milligrams instantly — with a full reference table below.
Convert Ounces to Milligrams
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How to convert Ounces to Milligrams
To convert ounces to milligrams, multiply by 28,349.52. One ounce equals 28,349.52 mg, and one milligram equals 0.000035274 oz.
- Take the value in ounces — for example 7.5 oz.
- Multiply by 28,349.52 (the number of milligrams in one ounce).
- 7.5 × 28,349.52 = 212,621.4 mg.
Ounces to Milligrams conversion table
| Ounces | Milligrams |
|---|---|
| 1 oz | 28,349.52 mg |
| 2 oz | 56,699.05 mg |
| 3 oz | 85,048.57 mg |
| 4 oz | 113,398.1 mg |
| 5 oz | 141,747.6 mg |
| 6 oz | 170,097.1 mg |
| 7 oz | 198,446.7 mg |
| 8 oz | 226,796.2 mg |
| 9 oz | 255,145.7 mg |
| 10 oz | 283,495.2 mg |
| 12 oz | 340,194.3 mg |
| 15 oz | 425,242.8 mg |
| 20 oz | 566,990.5 mg |
| 25 oz | 708,738.1 mg |
| 50 oz | 1,417,476 mg |
| 100 oz | 2,834,952 mg |
| Milligrams | Ounces |
|---|---|
| 1 mg | 0.000035274 oz |
| 2 mg | 0.0000705479 oz |
| 3 mg | 0.000105822 oz |
| 4 mg | 0.000141096 oz |
| 5 mg | 0.00017637 oz |
| 6 mg | 0.000211644 oz |
| 7 mg | 0.000246918 oz |
| 8 mg | 0.000282192 oz |
| 9 mg | 0.000317466 oz |
| 10 mg | 0.00035274 oz |
| 12 mg | 0.000423288 oz |
| 15 mg | 0.000529109 oz |
| 20 mg | 0.000705479 oz |
| 25 mg | 0.000881849 oz |
| 50 mg | 0.0017637 oz |
| 100 mg | 0.0035274 oz |
About converting Ounces to Milligrams
Ounces (oz) and Milligrams (mg) are both units of weight. The exact factor is 1 oz = 28,349.52 mg, so multiply by 28,349.52 to go from ounces to milligrams (or divide to go back).
The conversion runs entirely in your browser. Need the reverse? Use the Milligrams to Ounces converter, or the full unit converter for every unit at once.
Real-world weight in ounces and milligrams
| Example | Ounces | Milligrams |
|---|---|---|
| A US nickel coin | 0.17637 oz | 5,000 mg |
| 1 litre of water | ≈ 35.27396 oz | ≈ 1,000,000 mg |
| An Olympic men's barbell | 705.4792 oz | 20,000,000 mg |
| A typical checked-bag limit (economy) | ≈ 811.3011 oz | ≈ 23,000,000 mg |
“≈” marks typical values; the rest are defined or measured figures.
The units
The avoirdupois ounce: 1/16 of a pound, exactly 28.349523125 g.
Used for: US food packaging, postage and cooking.
One thousandth of a gram.
Used for: Medicine doses and nutrition labels.
These factors are exact: since 1959 the avoirdupois pound is defined as exactly 0.45359237 kg, and the ounce as 1/16 of that.