Mass and Weight · Unit Converter

Convert Femtogram to Milligram

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

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.

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.

Femtogram to Milligram conversion formula

The relationship between femtograms and milligrams:

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

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

How to use this converter

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

Step-by-step: convert femtograms to milligrams

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

Worked examples

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

Example 2 — Convert 100 fg to mg:
100 × 1e-12 = 1e-10 mg

Real-world example — Sub-visible-light wavelength

500 femtograms (the green-yellow visible band) equals 0.5 milligrams — the canonical conversion in optics between wavelength specifications and micron-scale lens-coating thicknesses.

500 fg × 1e-12 = 5e-10 mg

Real-world example — Spanning sub-micron to micron scale

Crossing from femtograms to milligrams is the everyday workflow of microscopy and semiconductor engineering — a measurement of 1000 femtograms translates to a much more compact value in milligrams that fits the scale of biological cells and process nodes.

1000 fg × 1e-12 = 1e-9 mg

Femtogram to Milligram conversion table

Standard reference values for converting femtograms to milligrams:

Femtogram [fg]Milligram [mg]
0.011e-14
0.11e-13
11e-12
22e-12
33e-12
44e-12
55e-12
101e-11
202e-11
303e-11
404e-11
505e-11
1001e-10
5005e-10
10001e-9

Frequently asked questions

How many milligrams is 1 femtogram?
1 femtogram equals 1e-12 milligram.
How do I convert femtograms to milligrams?
Multiply the value in femtograms by 1e-12 to get milligrams.
How do I convert milligrams back to femtograms?
Multiply the value in milligrams by 1e+12, or use the Milligram to Femtogram converter.
How many milligrams is 100 femtograms?
100 femtograms equals 1e-10 milligrams, because 100 × 1e-12 = 1e-10.

Convert Femtogram to other weight units

Show all Femtogram 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 fg = 1e-12 mg) verified against the following authoritative sources:

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