This converter turns milligrams into stones instantly, using the exact factor 1 milligram = 1.574730444e-07 stones. Type any number and the result updates as you go — nothing is sent to a server, so the arithmetic happens entirely in your browser.
One thousandth of a gram, the standard unit for medication doses and nutrients. Fourteen pounds — still the customary way to state body weight in the UK and Ireland.
Because the relationship is a simple proportion, one multiplication does the whole job. The table further down gives pre-computed values for the amounts people look up most often, and the result panel also reports the reverse conversion so you can check the figure both ways.
The formula
milligrams- The amount you are converting, measured in milligrams
1.574730444e-07- The exact number of stones in one milligram
stones- The converted result
How it works, step by step
- Enter the number of milligrams you want to convert.
- The value is multiplied by 1.574730444e-07, the exact conversion factor.
- The result is displayed in stones, rounded for readability.
- The unrounded value and the reverse conversion appear underneath so you can verify it.
Worked examples
Converting 5 milligrams
Multiply 5 by 1.5747304e-07. That gives 7.8737e-07 stones. A quick sanity check: one milligram is smaller than one stone, so the number should get smaller — and it does.
Converting 72 milligrams
72 × 1.5747304e-07 = 0.000011 stones. Working backwards, 0.000011 ÷ 1.5747304e-07 returns 72 milligrams, which confirms the factor is applied the right way round.
How to read your score
Frequently asked questions
How many stones are in one milligram?
Exactly 1.574730444e-07. Every conversion on this page is that single number multiplied by your input, so the result carries no rounding error beyond what is shown.
What is the formula to convert milligrams to stones?
Stones = milligrams × 1.574730444e-07. To reverse it, divide instead: milligrams = stones ÷ 1.574730444e-07, which is the same as multiplying by 6350293.18.
Is the milligram bigger than the stone?
No. One milligram is only 1.57473e-07 of a stone, so the stone is the larger unit.
Why does my answer differ slightly from other mg to stones converters?
Most differences come from rounding the factor too early. This tool keeps full double precision through the calculation and only rounds at the final display step, and it also shows the unrounded value so you can see exactly where any difference appears.
What is a milligram?
One thousandth of a gram, the standard unit for medication doses and nutrients.
What is a stone?
Fourteen pounds — still the customary way to state body weight in the UK and Ireland.
Milligrams to stones reference table
| Milligrams | Stones |
|---|---|
| 0.5 mg | 7.8737e-08 st |
| 1 mg | 1.5747e-07 st |
| 2 mg | 3.1495e-07 st |
| 3 mg | 4.7242e-07 st |
| 5 mg | 7.8737e-07 st |
| 10 mg | 0.000002 st |
| 15 mg | 0.000002 st |
| 20 mg | 0.000003 st |
| 25 mg | 0.000004 st |
| 50 mg | 0.000008 st |
| 75 mg | 0.000012 st |
| 100 mg | 0.000016 st |
| 250 mg | 0.000039 st |
| 500 mg | 0.000079 st |
| 1000 mg | 0.000157 st |
Exact factor: 1 milligram = 1.574730444e-07 stones. Values rounded for display.