Convert Carat (metric) to Ratti
Convert carats (metric) to rattis instantly. 1 carat (metric) = 1.646090535 ratti — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Ratti to Carat (metric) converter for the reverse conversion.
Units explained
Carat (metric)
The metric carat (ct) equals exactly 200 milligrams (0.0002 kg).
From Arabic 'qirat' and Greek 'keration', the carob seed once used as a counterweight.
The worldwide standard for gemstone and diamond mass.
The metric carat was fixed at 200 mg internationally in 1907.
Ratti
The ratti equals about 0.1215 gram, the smallest traditional South Asian weight.
Based on the seed of the Gunja plant (Abrus precatorius), or 'raktika' in Sanskrit.
Gemstones and gold in Indian and South Asian jewelry.
One of the oldest weight units of the Indian subcontinent, later standardized.
Carat (metric) to Ratti 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 rattis:
To convert carats (metric) to rattis, multiply the value in carats (metric) by 1.646090535. To reverse, multiply rattis by 0.6075.
How to use this converter
Type a value into the calculator. The result in rattis updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Ratti to Carat (metric) converter for the reverse direction.
Step-by-step: convert carats (metric) to rattis
- Write down the value in carats (metric) (ct).
- Multiply that value by the factor 1.646090535.
- The product is the equivalent value in rattis (ratti).
- To reverse, multiply the ratti value by 0.6075.
Worked examples
Example 1 — Convert 1 ct to ratti:
1 × 1.646090535 = 1.646090535 ratti
Example 2 — Convert 100 ct to ratti:
100 × 1.646090535 = 164.6090534979 ratti
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 rattis for direct comparison across supplier datasheets.
70 ct × 1.646090535 = 115.2263374486 ratti
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 × 1.646090535 = 4.9382716049 ratti
Real-world example — Plastic-film thickness alternates
A 150-carat (metric) plastic film converts cleanly to rattis — useful for packaging buyers reconciling supplier datasheets across metric and US measurement systems.
150 ct × 1.646090535 = 246.9135802469 ratti
Carat (metric) to Ratti conversion table
Standard reference values for converting carats (metric) to rattis:
| Carat (metric) [ct] | Ratti [ratti] |
|---|---|
| 0.01 | 0.0164609053 |
| 0.1 | 0.1646090535 |
| 1 | 1.646090535 |
| 2 | 3.29218107 |
| 3 | 4.9382716049 |
| 4 | 6.5843621399 |
| 5 | 8.2304526749 |
| 10 | 16.4609053498 |
| 20 | 32.9218106996 |
| 30 | 49.3827160494 |
| 40 | 65.8436213992 |
| 50 | 82.304526749 |
| 100 | 164.6090534979 |
| 500 | 823.0452674897 |
| 1000 | 1646.0905349794 |
Frequently asked questions
How many rattis is 1 carat (metric)?
How do I convert carats (metric) to rattis?
How do I convert rattis back to carats (metric)?
How many rattis is 100 carats (metric)?
Popular weight unit conversions
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)
Sources & references
Conversion factor (1 ct = 1.646090535 ratti) 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 Astronomical Union — System of Astronomical Constants
The IAU defines astronomical units including the AU (149597870700 m exactly) light-year and parsec used in astronomy and astrophysics.