Mass and Weight · Unit Converter

Convert Hectogram to Femtogram

Convert hectograms to femtograms instantly. 1 hectogram = 1e+17 femtogram — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Femtogram to Hectogram 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

Hectogram

What is a hectogram?

A hectogram (hg) equals 0.1 kilogram, or 100 grams.

Origin of the hectogram

From the SI prefix 'hecto-' (from Greek 'hekaton', hundred).

Where it is used

Common in continental European food retail, especially Italy ('etto').

When and where it was developed

The hecto- prefix dates to 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.

Hectogram to Femtogram conversion formula

The relationship between hectograms and femtograms:

1 hg = 1e+17 fg
1 fg = 1e-17 hg

To convert hectograms to femtograms, multiply the value in hectograms by 1e+17. To reverse, multiply femtograms by 1e-17.

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 Hectogram converter for the reverse direction.

Step-by-step: convert hectograms to femtograms

  1. Write down the value in hectograms (hg).
  2. Multiply that value by the factor 1e+17.
  3. The product is the equivalent value in femtograms (fg).
  4. To reverse, multiply the femtogram value by 1e-17.

Worked examples

Example 1 — Convert 1 hg to fg:
1 × 1e+17 = 1e+17 fg

Example 2 — Convert 100 hg to fg:
100 × 1e+17 = 1e+19 fg

Real-world example — Meter to nanoscale

One hectogram equals one billion femtograms. Physics curricula use this conversion to teach orders of magnitude when introducing the electromagnetic spectrum.

1 hg × 1e+17 = 1e+17 fg

Real-world example — Human-scale to atomic dimensions

One hectogram equals one billion femtograms — the canonical metric conversion bridging everyday objects and atomic-scale features in physics, chemistry, and electronics.

1 hg × 1e+17 = 1e+17 fg

Hectogram to Femtogram conversion table

Standard reference values for converting hectograms to femtograms:

Hectogram [hg]Femtogram [fg]
0.011e+15
0.11e+16
11e+17
22e+17
33e+17
44e+17
55e+17
101e+18
202e+18
303e+18
404e+18
505e+18
1001e+19
5005e+19
10001e+20

Frequently asked questions

How many femtograms is 1 hectogram?
1 hectogram equals 1e+17 femtogram.
How do I convert hectograms to femtograms?
Multiply the value in hectograms by 1e+17 to get femtograms.
How do I convert femtograms back to hectograms?
Multiply the value in femtograms by 1e-17, or use the Femtogram to Hectogram converter.
How many femtograms is 100 hectograms?
100 hectograms equals 1e+19 femtograms, because 100 × 1e+17 = 1e+19.

Convert Hectogram to other weight units

Show all Hectogram 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 hg = 1e+17 fg) verified against the following authoritative sources:

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