⚖️ Weight Converter

Ounces to Milligrams
( oz → mg )

Instantly convert ounces to milligrams. Enter any value below and get an accurate result with the full formula and reference table.

Converter Tool
oz
mg
Result
1 oz = 28,349.523125 mg
28,349.523125
mg
The Formula
mg = oz × 28,349.523125
1 ounce = 28.349523125 grams = 28,349.523125 milligrams. This relationship is exact.

How to Convert Ounces to Milligrams

To convert ounces to milligrams, multiply the number of ounces by 28,349.523125. This is because one ounce is equal to exactly 28.349523125 grams, and one gram is 1,000 milligrams.

Step-by-Step Example

Let’s convert 2 ounces to milligrams:

1. Multiply by 28,349.523125: 2 × 28,349.523125 = 56,699.04625
2. So 2 oz equals 56,699.05 mg.

For a smaller amount, 0.5 oz × 28,349.523125 = 14,174.7615625 mg.

When You’d Use Each Unit

Ounces are commonly used in the US for measuring food portions, postage, and small items. Milligrams are used for smaller masses, such as tablet weights or precise ingredient amounts in medicine and science. Converting between them helps understand the composition of products and ensures accurate dosing.

Conversion Table

Common ounces values converted to milligrams — typical values highlighted.

Ounces (oz) Milligrams (mg) Approximate
Frequently Asked Questions
How do I convert ounces to milligrams quickly? +
Multiply the number of ounces by 28,350 for a rough estimate. For exact conversion, use 28,349.523125. This tool provides the precise value.
How many milligrams are in an ounce? +
There are exactly 28,349.523125 milligrams in one ounce.
What is 1 oz in mg? +
1 oz = 28,349.523125 mg.
What is 1 mg in ounces? +
1 mg ≈ 3.5274e-5 oz.
What is 0.5 oz in mg? +
0.5 oz = 14,174.7615625 mg.
Can I convert milligrams back to ounces with this tool? +
Yes! Just type a value into the milligrams field and the ounces field updates automatically. Or use the ⇄ swap button to switch directions.
✓ Copied to clipboard!