Milligrams to Grams Converter
1 milligram (mg) equals 0.001 grams (g).
Quick answer
To convert milligrams to grams, divide by 1,000: 500 mg = 0.5 g.
- 1 milligram = 0.001 grams
- 1 gram = 1,000 milligrams
- Formula: g = mg ÷ 1,000
- Quick estimate: move the decimal point three places left: 250 mg = 0.25 g.
1 milligram = 0.001 grams
How to convert milligrams to grams
g = mg ÷ 1,000
To convert milligrams to grams, divide the number of milligrams by 1,000.
Example: 42 mg to g
- Start with the value in milligrams: 42 mg.
- Divide by 1,000: 42 ÷ 1,000 = 0.042.
- Result: 42 milligrams = 0.042 grams.
Going the other way, 1 gram = 1,000 milligrams, so to convert grams back to milligrams you multiply by the same number. See grams to milligrams.
Where the conversion factor comes from
The kilogram is the SI base unit of mass, defined since 2019 by fixing the value of the Planck constant. Metric prefixes are exact: 1 kg = 1,000 g, 1 g = 1,000 mg, and a metric tonne is 1,000 kg.
Mental math: mg to g in your head
Move the decimal point three places to the left.
When you need to convert milligrams to grams
- Medicine doses (a 500 mg tablet is 0.5 g).
- Nutrition labels (sodium, caffeine, vitamins).
Common mistakes
- Confusing mg with mcg (µg): 1 mg = 1,000 µg.
- Misreading a dose by a factor of 1,000 — always check units on medicine.
Everyday milligrams in grams
| Example | Milligrams | Grams |
|---|---|---|
| Low-dose aspirin | 81 mg | 0.081 g |
| Paracetamol tablet | 500 mg | 0.5 g |
| Caffeine in a cup of coffee | 95 mg | 0.095 g |
| Daily sodium limit (US guideline) | 2,300 mg | 2.3 g |
Milligrams to grams conversion table
| Milligrams (mg) | Grams (g) |
|---|---|
| 0.1 mg | 0.0001 g |
| 0.2 mg | 0.0002 g |
| 0.3 mg | 0.0003 g |
| 0.4 mg | 0.0004 g |
| 0.5 mg | 0.0005 g |
| 0.6 mg | 0.0006 g |
| 0.7 mg | 0.0007 g |
| 0.8 mg | 0.0008 g |
| 0.9 mg | 0.0009 g |
| 1 mg | 0.001 g |
| 1.5 mg | 0.0015 g |
| 2 mg | 0.002 g |
| 2.5 mg | 0.0025 g |
| 3 mg | 0.003 g |
| 3.5 mg | 0.0035 g |
| 4 mg | 0.004 g |
| 4.5 mg | 0.0045 g |
| 5 mg | 0.005 g |
| 6 mg | 0.006 g |
| 7 mg | 0.007 g |
| 7.5 mg | 0.0075 g |
| 8 mg | 0.008 g |
| 9 mg | 0.009 g |
| 10 mg | 0.01 g |
| 11 mg | 0.011 g |
| 12 mg | 0.012 g |
| 13 mg | 0.013 g |
| 14 mg | 0.014 g |
| 15 mg | 0.015 g |
| 16 mg | 0.016 g |
| 17 mg | 0.017 g |
| 18 mg | 0.018 g |
| 19 mg | 0.019 g |
| 20 mg | 0.02 g |
| 21 mg | 0.021 g |
| 22 mg | 0.022 g |
| 23 mg | 0.023 g |
| 24 mg | 0.024 g |
| 25 mg | 0.025 g |
| 26 mg | 0.026 g |
More mg to g values
- 27 mg
- 28 mg
- 29 mg
- 30 mg
- 31 mg
- 32 mg
- 33 mg
- 34 mg
- 35 mg
- 36 mg
- 37 mg
- 38 mg
- 39 mg
- 40 mg
- 41 mg
- 42 mg
- 43 mg
- 44 mg
- 45 mg
- 46 mg
- 47 mg
- 48 mg
- 49 mg
- 50 mg
- 51 mg
- 52 mg
- 53 mg
- 54 mg
- 55 mg
- 56 mg
- 57 mg
- 58 mg
- 59 mg
- 60 mg
- 61 mg
- 62 mg
- 63 mg
- 64 mg
- 65 mg
- 66 mg
- 67 mg
- 68 mg
- 69 mg
- 70 mg
- 71 mg
- 72 mg
- 73 mg
- 74 mg
- 75 mg
- 76 mg
- 77 mg
- 78 mg
- 79 mg
- 80 mg
- 81 mg
- 82 mg
- 83 mg
- 84 mg
- 85 mg
- 86 mg
- 87 mg
- 88 mg
- 89 mg
- 90 mg
- 91 mg
- 92 mg
- 93 mg
- 94 mg
- 95 mg
- 96 mg
- 97 mg
- 98 mg
- 99 mg
- 100 mg
- 110 mg
- 120 mg
- 130 mg
- 140 mg
- 150 mg
- 160 mg
- 170 mg
- 180 mg
- 190 mg
- 200 mg
- 210 mg
- 220 mg
- 230 mg
- 240 mg
- 250 mg
- 260 mg
- 270 mg
- 280 mg
- 290 mg
- 300 mg
- 310 mg
- 320 mg
- 330 mg
- 340 mg
- 350 mg
- 360 mg
- 370 mg
- 380 mg
- 390 mg
- 400 mg
- 410 mg
- 420 mg
- 430 mg
- 440 mg
- 450 mg
- 460 mg
- 470 mg
- 480 mg
- 490 mg
- 500 mg
- 600 mg
- 700 mg
- 800 mg
- 900 mg
- 1,000 mg
- 1,200 mg
- 1,500 mg
- 2,000 mg
- 2,500 mg
- 3,000 mg
- 4,000 mg
- 5,000 mg
- 10,000 mg
What is a milligram?
The milligram is a metric unit of mass equal to one thousandth of a gram.
What is a gram?
The gram is a metric unit of mass equal to one thousandth of a kilogram.
Convert milligrams to other units
Convert other units to grams
Frequently asked questions
How many grams are in a milligram?
One milligram is 0.001 grams.
How many milligrams are in a gram?
One gram is 1,000 milligrams.
What is the formula to convert milligrams to grams?
g = mg ÷ 1,000.
How many mg in a gram?
1,000 milligrams.