Mass and Weight · Unit Converter

Convert Carat (metric) to Wey

Convert carats (metric) to weys instantly. 1 carat (metric) = 1.7497e-6 wey — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Wey 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 Last reviewed Updated

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.

Avoirdupois

Wey

What is a wey?

The wey was an English bulk weight, here taken as 252 pounds (about 114.3 kg).

Origin of the wey

From Old English 'waege', a weighing or balance.

Where it is used

Obsolete English unit for wool, cheese, and salt.

When and where it was developed

Used in medieval and early-modern English trade.

Carat (metric) to Wey conversion formula

Note: this conversion uses a generally accepted modern value. Historical and regional definitions of this unit varied across times and places.

The relationship between carats (metric) and weys:

1 ct = 1.7497e-6 wey
1 wey = 571526.3861999999 ct

To convert carats (metric) to weys, multiply the value in carats (metric) by 1.7497e-6. To reverse, multiply weys by 571526.3861999999.

How to use this converter

Type a value into the calculator. The result in weys updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Wey to Carat (metric) converter for the reverse direction.

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

  1. Write down the value in carats (metric) (ct).
  2. Multiply that value by the factor 1.7497e-6.
  3. The product is the equivalent value in weys (wey).
  4. To reverse, multiply the wey value by 571526.3861999999.

Worked examples

Example 1 — Convert 1 ct to wey:
1 × 1.7497e-6 = 1.7497e-6 wey

Example 2 — Convert 100 ct to wey:
100 × 1.7497e-6 = 0.00017497 wey

Real-world example — Plastic-film thickness alternates

A 150-carat (metric) plastic film converts cleanly to weys — useful for packaging buyers reconciling supplier datasheets across metric and US measurement systems.

150 ct × 1.7497e-6 = 0.0002624551 wey

Real-world example — Hair-width scale measurements

A 70-carat (metric) measurement (about the diameter of a human hair) is the kind of value materials engineers regularly express in adjacent micro-scale units like weys for direct comparison across supplier datasheets.

70 ct × 1.7497e-6 = 0.000122479 wey

Real-world example — Paper and film thicknesses

At the thickness of office paper (roughly 3 carats (metric)), converting between sub-millimeter units is routine for packaging and printing buyers comparing quotes from metric and US suppliers.

3 ct × 1.7497e-6 = 5.249101e-6 wey

Carat (metric) to Wey conversion table

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

Carat (metric) [ct]Wey [wey]
0.011.7497e-8
0.11.7497e-7
11.7497e-6
23.499401e-6
35.249101e-6
46.998802e-6
58.748502e-6
101.7497e-5
203.499401e-5
305.249101e-5
406.998802e-5
508.748502e-5
1000.00017497
5000.0008748502
10000.0017497005

Frequently asked questions

How many weys is 1 carat (metric)?
1 carat (metric) equals 1.7497e-6 wey.
How do I convert carats (metric) to weys?
Multiply the value in carats (metric) by 1.7497e-6 to get weys.
How do I convert weys back to carats (metric)?
Multiply the value in weys by 571526.3861999999, or use the Wey to Carat (metric) converter.
How many weys is 100 carats (metric)?
100 carats (metric) equals 0.00017497 weys, because 100 × 1.7497e-6 = 0.00017497.

Convert Carat (metric) to other weight units

Show all Carat (metric) conversions
Metric / SI (18 units)
Avoirdupois (15 units)
Troy & Apothecary (9 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 ct = 1.7497e-6 wey) verified against the following authoritative sources:

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