Mass and Weight · Unit Converter

Convert Stone (UK) to Carat (metric)

Convert stones (uk) to carats (metric) instantly. 1 stone (uk) = 31751.4659 carat (metric) — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Carat (metric) to Stone (UK) 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

Avoirdupois

Stone (UK)

What is a stone (uk)?

The UK stone (st) equals 14 pounds, about 6.35 kilograms.

Origin of the stone (uk)

From standardized market 'stones' once used for weighing goods.

Where it is used

Body weight in the United Kingdom and Ireland.

When and where it was developed

Fixed at 14 pounds by British statute in 1835.

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.

Stone (UK) to Carat (metric) conversion formula

The relationship between stones (uk) and carats (metric):

1 st = 31751.4659 ct
1 ct = 3.149461e-5 st

To convert stones (uk) to carats (metric), multiply the value in stones (uk) by 31751.4659. To reverse, multiply carats (metric) by 3.149461e-5.

How to use this converter

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

Step-by-step: convert stones (uk) to carats (metric)

  1. Write down the value in stones (uk) (st).
  2. Multiply that value by the factor 31751.4659.
  3. The product is the equivalent value in carats (metric) (ct).
  4. To reverse, multiply the carat (metric) value by 3.149461e-5.

Worked examples

Example 1 — Convert 1 st to ct:
1 × 31751.4659 = 31751.4659 ct

Example 2 — Convert 100 st to ct:
100 × 31751.4659 = 3175146.5899999999 ct

Real-world example — Sub-meter precision

A 0.001-stone (uk) (1 mm) tolerance equals 1,000 carats (metric) — useful for surface-finish specs, where macro-scale dimensions are given in the larger unit but feature roughness in the smaller.

0.001 st × 31751.4659 = 31.7514659 ct

Real-world example — Macro-to-micro scale comparison

2 stones (uk) of measurement converts to a very large number in carats (metric) — useful in materials science when comparing bulk-sample dimensions to feature-level surface specs.

2 st × 31751.4659 = 63502.9318 ct

Real-world example — Macroscopic to microscopic

One stone (uk) equals a million carats (metric). Optical engineers calculating coherence length compare macro-scale path lengths with micro-scale wavelength differences using exactly this conversion.

1 st × 31751.4659 = 31751.4659 ct

Stone (UK) to Carat (metric) conversion table

Standard reference values for converting stones (uk) to carats (metric):

Stone (UK) [st]Carat (metric) [ct]
0.01317.514659
0.13175.14659
131751.4659
263502.9318
395254.3977
4127005.8636
5158757.3295
10317514.659
20635029.318
30952543.977
401270058.6359999999
501587573.2949999999
1003175146.5899999999
5001.587573e+7
10003.175147e+7

Frequently asked questions

How many carats (metric) is 1 stone (uk)?
1 stone (uk) equals 31751.4659 carat (metric).
How do I convert stones (uk) to carats (metric)?
Multiply the value in stones (uk) by 31751.4659 to get carats (metric).
How do I convert carats (metric) back to stones (uk)?
Multiply the value in carats (metric) by 3.149461e-5, or use the Carat (metric) to Stone (UK) converter.
How many carats (metric) is 100 stones (uk)?
100 stones (uk) equals 3175146.5899999999 carats (metric), because 100 × 31751.4659 = 3175146.5899999999.

Convert Stone (UK) to other weight units

Show all Stone (UK) conversions
Metric / SI (18 units)
Stone (UK) to Attogram (ag) Stone (UK) to Femtogram (fg) Stone (UK) to Picogram (pg) Stone (UK) to Nanogram (ng) Stone (UK) to Microgram (µg) Stone (UK) to Milligram (mg) Stone (UK) to Centigram (cg) Stone (UK) to Decigram (dg) Stone (UK) to Gram (g) Stone (UK) to Dekagram (dag) Stone (UK) to Hectogram (hg) Stone (UK) to Kilogram (kg) Stone (UK) to Quintal (metric) (q) Stone (UK) to Metric Ton (t) Stone (UK) to Gigagram (Gg) Stone (UK) to Teragram (Tg) Stone (UK) to Petagram (Pg) Stone (UK) to Exagram (Eg)
Avoirdupois (14 units)
Stone (UK) to Grain (gr) Stone (UK) to Dram (avoirdupois) (dr) Stone (UK) to Ounce (oz) Stone (UK) to Pound (lb) Stone (UK) to Clove (clove) Stone (UK) to Stone (US) (st) Stone (UK) to Quarter (US) (qr) Stone (UK) to Quarter (UK) (qr) Stone (UK) to Hundredweight (US) (cwt) Stone (UK) to Hundredweight (UK) (cwt) Stone (UK) to Wey (wey) Stone (UK) to Kilopound (kip) (kip) Stone (UK) to Ton (short, US) (sh tn) Stone (UK) to Ton (long, UK) (long tn)
Troy & Apothecary (10 units)
Stone (UK) to Point (1/100 carat) (pt) Stone (UK) to Carat (metric) (ct) Stone (UK) to Scruple (apothecary) (s ap) Stone (UK) to Pennyweight (dwt) Stone (UK) to Momme (mom) Stone (UK) to Mace (mace) Stone (UK) to Dram (apothecary/troy) (dr ap) Stone (UK) to Troy Ounce (oz t) Stone (UK) to Tael (tael) Stone (UK) to Pound (troy/apothecary) (lb t)
Indian / South Asian (6 units)
Stone (UK) to Ratti (ratti) Stone (UK) to Masha (masha) Stone (UK) to Tola (tola) Stone (UK) to Chittack (Chatank) (chittack) Stone (UK) to Seer (Ser) (seer) Stone (UK) to Maund (Mann) (maund)
Scientific / Atomic (9 units)
Stone (UK) to Electron Mass (rest) (me) Stone (UK) to MeV/c2 (MeV/c²) Stone (UK) to Muon Mass (mµ) Stone (UK) to Atomic Mass Unit (u) Stone (UK) to Proton Mass (mp) Stone (UK) to Neutron Mass (mn) Stone (UK) to Deuteron Mass (md) Stone (UK) to Carbon-12 Atom Mass (C-12) Stone (UK) to Planck Mass (mP)
Astronomical (4 units)
Stone (UK) to Lunar Mass (Moon) (M☾) Stone (UK) to Earth's Mass (M⊕) Stone (UK) to Jupiter Mass (MJ) Stone (UK) to Sun's Mass (M☉)
Biblical / Ancient (14 units)
Stone (UK) to Lepton (Biblical Roman) (lepton) Stone (UK) to Quadrans (Biblical Roman) (quadrans) Stone (UK) to Assarion (Biblical Roman) (assarion) Stone (UK) to Gerah (Biblical Hebrew) (gerah) Stone (UK) to Drachma (Biblical Greek) (drachma) Stone (UK) to Denarius (Biblical Roman) (denarius) Stone (UK) to Bekan (Biblical Hebrew) (bekah) Stone (UK) to Didrachma (Biblical Greek) (didrachma) Stone (UK) to Shekel (Biblical Hebrew) (shekel) Stone (UK) to Tetradrachma (Biblical Greek) (tetra) Stone (UK) to Mina (Biblical Greek) (mina) Stone (UK) to Mina (Biblical Hebrew) (mina) Stone (UK) to Talent (Biblical Greek) (talent) Stone (UK) to Talent (Biblical Hebrew) (talent)
Force / Engineering (5 units)
Stone (UK) to Poundal (pdl) Stone (UK) to Ton (assay) (US) (AT) Stone (UK) to Ton (assay) (UK) (AT) Stone (UK) to Kilogram-force square second/meter (hyl) Stone (UK) to Slug (slug)

Sources & references

Conversion factor (1 st = 31751.4659 ct) verified against the following authoritative sources:

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