Mass and Weight · Unit Converter

Convert Milligram to Femtogram

Convert milligrams to femtograms instantly. 1 milligram = 1e+12 femtogram — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Femtogram to Milligram converter for the reverse conversion.

Written by Sunith Babu L, Ph.D., Lead Engineer Reviewed by Dr. Ashok Kumar K, Ph.D.
Mass and Weight category 2 min read Published Last reviewed Updated

Units explained

Metric / SI

Milligram

What is a milligram?

A milligram (mg) equals one-millionth of a kilogram, or 0.001 gram.

Origin of the milligram

From the SI prefix 'milli-' (from Latin 'mille', thousand).

Where it is used

Standard for medicine dosing, nutrition labels, and fine jewelry.

When and where it was developed

Part of the original metric system of 1795.

Metric / SI

Femtogram

What is a femtogram?

A femtogram (fg) equals 10^-18 kilogram.

Origin of the femtogram

From the SI prefix 'femto-' (from Danish/Norwegian 'femten', fifteen).

Where it is used

Nanotechnology and high-sensitivity mass spectrometry.

When and where it was developed

The femto- prefix was adopted by the CGPM in 1975.

Milligram to Femtogram conversion formula

The relationship between milligrams and femtograms:

1 mg = 1e+12 fg
1 fg = 1e-12 mg

To convert milligrams to femtograms, multiply the value in milligrams by 1e+12. To reverse, multiply femtograms by 1e-12.

How to use this converter

Type a value into the calculator. The result in femtograms updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Femtogram to Milligram converter for the reverse direction.

Step-by-step: convert milligrams to femtograms

  1. Write down the value in milligrams (mg).
  2. Multiply that value by the factor 1e+12.
  3. The product is the equivalent value in femtograms (fg).
  4. To reverse, multiply the femtogram value by 1e-12.

Worked examples

Example 1 — Convert 1 mg to fg:
1 × 1e+12 = 1e+12 fg

Example 2 — Convert 100 mg to fg:
100 × 1e+12 = 1e+14 fg

Real-world example — Mid-micron to nanometer

3 milligrams equals 3,000 femtograms — useful when relating mid-infrared wavelengths (typically quoted in microns) to nanometer-scale visible-light wavelength tables.

3 mg × 1e+12 = 3e+12 fg

Real-world example — From microns to sub-micron features

One milligram equals one thousand femtograms — the conversion semiconductor designers do constantly when comparing mask feature dimensions to actual transistor gate lengths.

1 mg × 1e+12 = 1e+12 fg

Real-world example — Infrared to visible-spectrum mapping

A 10-milligram thermal infrared wavelength corresponds to a much larger number in femtograms, the unit favoured for ultraviolet and visible-light specifications.

10 mg × 1e+12 = 1e+13 fg

Milligram to Femtogram conversion table

Standard reference values for converting milligrams to femtograms:

Milligram [mg]Femtogram [fg]
0.011e+10
0.11e+11
11e+12
22e+12
33e+12
44e+12
55e+12
101e+13
202e+13
303e+13
404e+13
505e+13
1001e+14
5005e+14
10001e+15

Frequently asked questions

How many femtograms is 1 milligram?
1 milligram equals 1e+12 femtogram.
How do I convert milligrams to femtograms?
Multiply the value in milligrams by 1e+12 to get femtograms.
How do I convert femtograms back to milligrams?
Multiply the value in femtograms by 1e-12, or use the Femtogram to Milligram converter.
How many femtograms is 100 milligrams?
100 milligrams equals 1e+14 femtograms, because 100 × 1e+12 = 1e+14.

Convert Milligram to other weight units

Show all Milligram conversions
Metric / SI (17 units)
Avoirdupois (15 units)
Troy & Apothecary (10 units)
Indian / South Asian (6 units)
Scientific / Atomic (9 units)
Astronomical (4 units)
Biblical / Ancient (14 units)
Force / Engineering (5 units)

Sources & references

Conversion factor (1 mg = 1e+12 fg) verified against the following authoritative sources:

Results are provided for general reference. Verify critical measurements against an authoritative standard.