Weight & Mass

Milligrams to Micrograms

Convert milligrams to micrograms instantly. 1 mg = 1000 µg. Includes the exact factor, a conversion table of common values and the definition of both units.

mg
Micrograms

How to convert milligrams to micrograms

To convert milligrams to micrograms, multiply by 1000. The relationship is fixed, so the same factor works for any quantity — there is nothing to look up and nothing that changes with temperature, location or context.

µg = mg × 1000

Milligrams to Micrograms conversion table

The values people look up most often, rounded for reading. Use the calculator above for anything in between.

MilligramsMicrograms
1 mg1000 µg
2 mg2,000 µg
3 mg3,000 µg
5 mg5,000 µg
10 mg10,000 µg
20 mg20,000 µg
25 mg25,000 µg
50 mg50,000 µg
100 mg100,000 µg
500 mg500,000 µg
1,000 mg1,000,000 µg

What is a milligram?

A thousandth of a gram. Standard for medication strength.

What is a microgram?

A millionth of a gram. The unit for vitamin doses and trace contaminants.

The formula

µg = mg × 1000

Every result on this page comes from this formula. Nothing is rounded until the final display, so figures match a spreadsheet to the cent.

How to use the Milligrams to Micrograms

  1. Type the number of milligrams you want to convert.
  2. Read the result in micrograms straight away — there is no button to press.
  3. Check the table below for the values that come up most often, or reverse the conversion with the linked micrograms to milligrams page.

Milligrams to Micrograms — frequently asked questions

How many micrograms are in a milligram?

One milligram equals 1000 µg. µg = mg × 1000

What is the formula to convert milligrams to micrograms?

The formula is µg = mg × 1000. It is an exact definition rather than an approximation, so the conversion never drifts no matter how large the number.

How do I convert micrograms back to milligrams?

Divide instead of multiplying: one microgram is 0.001 mg. The reverse converter is linked in the related tools list.

Is this conversion exact?

Yes. Both units are defined against the same base unit by international agreement, so the factor is exact — any rounding you see is only in the display, which you can widen by entering more decimal places.

Is this milligrams to micrograms free to use?

Yes. Every calculator on the site is free, needs no sign-up, and runs entirely in your browser, so your figures never leave your device.

What people search for

This page answers each of these searches. They are the exact phrases visitors use to find the milligrams to micrograms.

  • milligrams to micrograms
  • milligrams to micrograms converter
  • convert milligrams to micrograms
  • mg to ug
  • mg to mcg
  • mg to micrograms
  • milligrams to ug
  • milligrams to mcg

About this calculator

Written and reviewed by The Samsung Calculator editorial team. Every calculator is written against a published formula, reviewed against at least one independent reference implementation, and dated when it changes.

Last reviewed August 15, 2026 · Calculation runs client-side · No data collected · Report an error