Mass and Weight · Unit Converter

Convert Carat (metric) to Hectogram

Convert carats (metric) to hectograms instantly. 1 carat (metric) = 0.002 hectogram — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Hectogram to Carat (metric) 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 June 10, 2026 Last reviewed June 10, 2026 Updated June 10, 2026

Units explained

Troy & Apothecary

Carat (metric)

What is a carat (metric)?

The metric carat (ct) equals exactly 200 milligrams (0.0002 kg).

Origin of the carat (metric)

From Arabic 'qirat' and Greek 'keration', the carob seed once used as a counterweight.

Where it is used

The worldwide standard for gemstone and diamond mass.

When and where it was developed

The metric carat was fixed at 200 mg internationally in 1907.

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.

Carat (metric) to Hectogram conversion formula

The relationship between carats (metric) and hectograms:

1 ct = 0.002 hg

1 hg = 500 ct

To convert carats (metric) to hectograms, multiply the value in carats (metric) by 0.002. To reverse, multiply hectograms by 500.

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 Carat (metric) converter for the reverse direction.

Step-by-step: convert carats (metric) to hectograms

Write down the value in carats (metric) (ct).
Multiply that value by the factor 0.002.
The product is the equivalent value in hectograms (hg).
To reverse, multiply the hectogram value by 500.

Worked examples

Example 1 — Convert 1 ct to hg:
1 × 0.002 = 0.002 hg

Example 2 — Convert 100 ct to hg:
100 × 0.002 = 0.2 hg

Real-world example — Quarter-meter measurement reference

A 250,000-carat (metric) length equals 0.25 hectograms — useful for comparing supply-chain spec sheets where some lengths are quoted in the smaller unit and some in the larger.

250000 ct × 0.002 = 500 hg

Real-world example — From microscopic to macroscopic

A million carats (metric) equals exactly one hectogram. This kind of conversion appears in microfluidics, where total channel length is given in hectograms but feature widths are in carats (metric).

1000000 ct × 0.002 = 2000 hg

Real-world example — Macro-scale buildup

A million carats (metric) equals exactly one hectogram — the conversion that bridges microscale features and macroscale objects in microfluidic, biomedical, and semiconductor packaging design.

1000000 ct × 0.002 = 2000 hg

Carat (metric) to Hectogram conversion table

Standard reference values for converting carats (metric) to hectograms:

Carat (metric) [ct]	Hectogram [hg]
0.01	2e-5
0.1	0.0002
1	0.002
2	0.004
3	0.006
4	0.008
5	0.01
10	0.02
20	0.04
30	0.06
40	0.08
50	0.1
100	0.2
500	1
1000	2

Frequently asked questions

How many hectograms is 1 carat (metric)?

1 carat (metric) equals 0.002 hectogram.

How do I convert carats (metric) to hectograms?

Multiply the value in carats (metric) by 0.002 to get hectograms.

How do I convert hectograms back to carats (metric)?

Multiply the value in hectograms by 500, or use the Hectogram to Carat (metric) converter.

How many hectograms is 100 carats (metric)?

100 carats (metric) equals 0.2 hectograms, because 100 × 0.002 = 0.2.

Convert Carat (metric) to other weight units

Show all Carat (metric) conversions

Metric / SI (18 units)

Avoirdupois (15 units)

Troy & Apothecary (9 units)

Carat (metric) to Point (1/100 carat) (pt) Carat (metric) to Scruple (apothecary) (s ap) Carat (metric) to Pennyweight (dwt) Carat (metric) to Momme (mom) Carat (metric) to Mace (mace) Carat (metric) to Dram (apothecary/troy) (dr ap) Carat (metric) to Troy Ounce (oz t) Carat (metric) to Tael (tael) Carat (metric) to Pound (troy/apothecary) (lb t)

Indian / South Asian (6 units)

Carat (metric) to Ratti (ratti) Carat (metric) to Masha (masha) Carat (metric) to Tola (tola) Carat (metric) to Chittack (Chatank) (chittack) Carat (metric) to Seer (Ser) (seer) Carat (metric) to Maund (Mann) (maund)

Scientific / Atomic (9 units)

Carat (metric) to Electron Mass (rest) (me) Carat (metric) to MeV/c2 (MeV/c²) Carat (metric) to Muon Mass (mµ) Carat (metric) to Atomic Mass Unit (u) Carat (metric) to Proton Mass (mp) Carat (metric) to Neutron Mass (mn) Carat (metric) to Deuteron Mass (md) Carat (metric) to Carbon-12 Atom Mass (C-12) Carat (metric) to Planck Mass (mP)

Astronomical (4 units)

Carat (metric) to Lunar Mass (Moon) (M☾) Carat (metric) to Earth's Mass (M⊕) Carat (metric) to Jupiter Mass (MJ) Carat (metric) to Sun's Mass (M☉)

Biblical / Ancient (14 units)

Carat (metric) to Lepton (Biblical Roman) (lepton) Carat (metric) to Quadrans (Biblical Roman) (quadrans) Carat (metric) to Assarion (Biblical Roman) (assarion) Carat (metric) to Gerah (Biblical Hebrew) (gerah) Carat (metric) to Drachma (Biblical Greek) (drachma) Carat (metric) to Denarius (Biblical Roman) (denarius) Carat (metric) to Bekan (Biblical Hebrew) (bekah) Carat (metric) to Didrachma (Biblical Greek) (didrachma) Carat (metric) to Shekel (Biblical Hebrew) (shekel) Carat (metric) to Tetradrachma (Biblical Greek) (tetra) Carat (metric) to Mina (Biblical Greek) (mina) Carat (metric) to Mina (Biblical Hebrew) (mina) Carat (metric) to Talent (Biblical Greek) (talent) Carat (metric) to Talent (Biblical Hebrew) (talent)

Force / Engineering (5 units)

Carat (metric) to Poundal (pdl) Carat (metric) to Ton (assay) (US) (AT) Carat (metric) to Ton (assay) (UK) (AT) Carat (metric) to Kilogram-force square second/meter (hyl) Carat (metric) to Slug (slug)

Sources & references

Conversion factor (1 ct = 0.002 hg) verified against the following authoritative sources:

BIPM — The International System of Units (SI Brochure 9th ed.)
Official BIPM publication defining the seven SI base units (including the meter) and the rules for their use. The global authority on units of measurement.
NIST — Guide to the SI
US National Institute of Standards and Technology reference covering the SI base and derived units with definitions and usage rules for US technical practice.
NIST Special Publication 811 — Guide for the Use of the International System of Units
Detailed NIST guide covering exact conversion factors between SI and US customary units along with formatting and rounding conventions.
NIST — Refinement of values for the yard and pound (Federal Register 1959)
The treaty (signed by US
International Hydrographic Organization — Resolution on the Nautical Mile
International authority that standardised the nautical mile at exactly 1852 m in 1929 — the value adopted worldwide for sea and air navigation.

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