Mass and Weight · Unit Converter

Convert Attogram to Hectogram

Convert attograms to hectograms instantly. 1 attogram = 1e-20 hectogram — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Hectogram to Attogram 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

Attogram

What is a attogram?

An attogram (ag) equals 10^-21 kilogram.

Origin of the attogram

From the SI prefix 'atto-' (from Danish 'atten', eighteen).

Where it is used

Frontier nanoscience and single-molecule mass detection.

When and where it was developed

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

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.

Attogram to Hectogram conversion formula

The relationship between attograms and hectograms:

1 ag = 1e-20 hg
1 hg = 1e+20 ag

To convert attograms to hectograms, multiply the value in attograms by 1e-20. To reverse, multiply hectograms by 1e+20.

How to use this converter

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

Step-by-step: convert attograms to hectograms

  1. Write down the value in attograms (ag).
  2. Multiply that value by the factor 1e-20.
  3. The product is the equivalent value in hectograms (hg).
  4. To reverse, multiply the hectogram value by 1e+20.

Worked examples

Example 1 — Convert 1 ag to hg:
1 × 1e-20 = 1e-20 hg

Example 2 — Convert 100 ag to hg:
100 × 1e-20 = 1e-18 hg

Real-world example — From sub-micron to human scale

One billion attograms equals one hectogram — the conversion that drives home the gulf between atomic-scale features and everyday objects in physics curricula.

1e+9 ag × 1e-20 = 1e-11 hg

Real-world example — Bridging nine orders of magnitude

500 million attograms equals a value comfortably in the human-scale hectograms range. Physics problems that span this gap are common when comparing the wavelength of light to the path length of an experiment.

5e+8 ag × 1e-20 = 5e-12 hg

Attogram to Hectogram conversion table

Standard reference values for converting attograms to hectograms:

Attogram [ag]Hectogram [hg]
0.011e-22
0.11e-21
11e-20
22e-20
33e-20
44e-20
55e-20
101e-19
202e-19
303e-19
404e-19
505e-19
1001e-18
5005e-18
10001e-17

Frequently asked questions

How many hectograms is 1 attogram?
1 attogram equals 1e-20 hectogram.
How do I convert attograms to hectograms?
Multiply the value in attograms by 1e-20 to get hectograms.
How do I convert hectograms back to attograms?
Multiply the value in hectograms by 1e+20, or use the Hectogram to Attogram converter.
How many hectograms is 100 attograms?
100 attograms equals 1e-18 hectograms, because 100 × 1e-20 = 1e-18.

Convert Attogram to other weight units

Show all Attogram 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 ag = 1e-20 hg) verified against the following authoritative sources:

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