About mgtomcg.com
This page explains what mgtomcg.com is, who runs it and how it works.
What this site is
mgtomcg.com is a free converter for small metric units: grams, milligrams, micrograms and nanograms. It also has plain guides to the units you see on labels, like mcg, mcg RAE and IU.
It is an independent education project. It does not sell anything, it shows no ads and it needs no sign up.
How the math works
The converters work on the digits you type, as text. They move the decimal point, so 0.1 + 0.2 style rounding errors cannot happen. When a result does need rounding, as with some IU values, the page says so next to the answer.
Every table on the site, like the common values grids and the chart, is made by the same math when the site is built. No value is typed by hand.
Where the facts come from
- Unit sizes and prefixes: NIST, the US National Institute of Standards and Technology.
- Safe ways to write numbers and units: the Institute for Safe Medication Practices (ISMP) list of error prone abbreviations.
- Label units and IU factors: the FDA's 2019 label guide and the federal rule for supplement labels, 21 CFR 101.36.
Each page lists its sources with the date they were read.
What this site does not do
- It does not give doses, amounts to take or advice of any kind.
- It does not name, sell or rank any product.
- It does not do medicine math or read lab results.
Education only. Not medical advice.
Contact and corrections
If you find a mistake, write to help@mgtomcg.com. We fix errors and change the date at the top of the page when we do.