How many milligrams are in one ounce?

One avoirdupois ounce equals exactly 28,349.523125 milligrams. This is the standard ounce used for everyday weights. The troy ounce (used for precious metals) is slightly heavier at 31,103.4768 mg.

Is this avoirdupois ounce or troy ounce?

This tool converts to the avoirdupois ounce (the common ounce used in the US and UK for food, body weight, and general goods). If you need troy ounces, divide the milligram value by 31,103.4768 instead.

How do I convert milligrams to grams?

Divide the milligram value by 1,000. For example, 5,000 mg = 5 g. This converter shows both ounces and grams side by side for convenience.

Can I enter decimal milligram values?

Yes. The input accepts any positive decimal number, including very small values like 0.5 mg or 0.001 mg.

How accurate are the results?

Results are computed with full JavaScript floating-point precision and displayed to six significant figures, which is sufficient for virtually all practical purposes.

Milligrams to Ounces Converter

Type a milligram value and instantly see the equivalent in ounces and grams.

Enter Milligrams

Milligrams (mg)

Quick Reference

mg	oz	g

Results

Ounces (oz)

—

Grams (g)

—

Formula: oz = mg ÷ 28,349.523125 | g = mg ÷ 1,000

Copied!

Summary

This converter turns milligrams (mg) into ounces (oz avoirdupois) and grams (g) in real time, entirely in your browser. One avoirdupois ounce equals exactly 28,349.523125 milligrams, which is the conversion factor used here. Results are rounded to six significant figures to keep them accurate yet readable.

How it works

Enter the milligram value in the input field.
The converter divides your value by 28,349.523125 to get ounces.
It also divides by 1,000 to show the equivalent in grams.
Results update instantly as you type — no button press needed.
Use the Copy button to copy either result to your clipboard.

Use cases

Convert supplement or medication doses listed in mg to oz.
Scale cooking or baking recipes between metric and imperial units.
Verify postal or shipping weights when switching unit systems.
Check jewelry or precious-metal weights during purchase.
Educational use for unit-conversion practice.
Cross-check lab measurements between mg and oz.

Frequently Asked Questions

Last updated: 2026-10-05 · Reviewed by Nham Vu