Ounce to Milligram Converter
1 oz = 28,349.523125 mg — convert instantly with formula and table.
Type a value above and it converts instantly — no button to press, no page reload, and the math runs entirely in your browser.
Quick answer: one ounce equals 28,349.52 milligrams. So to convert ounces to milligrams, multiply by 28,349.523125.
How to convert ounces to milligrams
milligrams = ounces × 28,349.523125
The avoirdupois ounce is exactly 28.349523125 grams. It dominates American recipe and food-label weights and is one sixteenth of a pound.
The milligram — one thousandth of a gram — is the unit of medicine dosages and nutrition labels, where tiny quantities matter enormously.
Ounce to Milligram conversion table
| Ounce (oz) | Milligram (mg) |
|---|---|
| 0.01 oz | 283.4952 mg |
| 0.1 oz | 2,834.95 mg |
| 0.25 oz | 7,087.38 mg |
| 0.4 oz | 11,339.81 mg |
| 0.75 oz | 21,262.14 mg |
| 1.25 oz | 35,436.9 mg |
| 1.75 oz | 49,611.67 mg |
| 2.5 oz | 70,873.81 mg |
| 3.5 oz | 99,223.33 mg |
| 4.5 oz | 127,572.85 mg |
| 6 oz | 170,097.14 mg |
| 8 oz | 226,796.19 mg |
| 10 oz | 283,495.23 mg |
| 12 oz | 340,194.28 mg |
| 14 oz | 396,893.32 mg |
| 16 oz | 453,592.37 mg |
| 18 oz | 510,291.42 mg |
| 20 oz | 566,990.46 mg |
| 24 oz | 680,388.56 mg |
| 26 oz | 737,087.6 mg |
| 30 oz | 850,485.69 mg |
| 35 oz | 992,233.31 mg |
| 45 oz | 1,275,728.54 mg |
| 55 oz | 1,559,223.77 mg |
| 65 oz | 1,842,719 mg |
| 75 oz | 2,126,214.23 mg |
| 85 oz | 2,409,709.47 mg |
| 95 oz | 2,693,204.7 mg |
| 110 oz | 3,118,447.54 mg |
| 125 oz | 3,543,690.39 mg |
| 175 oz | 4,961,166.55 mg |
| 250 oz | 7,087,380.78 mg |
| 350 oz | 9,922,333.09 mg |
| 450 oz | 12,757,285.41 mg |
| 600 oz | 17,009,713.88 mg |
| 750 oz | 21,262,142.34 mg |
| 900 oz | 25,514,570.81 mg |
| 1,500 oz | 42,524,284.69 mg |
| 2,500 oz | 70,873,807.81 mg |
| 10,000 oz | 283,495,231.25 mg |
Need the opposite direction? Use the Milligram to Ounce converter, or read our complete guide to weight conversions for every formula in one place.
Frequently asked questions
How many milligrams are in one ounce?
One ounce equals 28,349.52 milligrams. Multiply any ounce value by 28,349.523125 to get milligrams.
What is 10 ounces in milligrams?
10 ounces equal 283,495.23 milligrams (10 × 28,349.523125).
Is the ounce to milligram conversion exact?
The conversion factor used here (28,349.523125) is based on the internationally agreed definitions of both units, so results are exact up to rounding of the final decimal places.
Is my data stored when I use this converter?
No. The conversion runs entirely in your browser with JavaScript — nothing you type is sent to a server, logged or stored.