Weight / Mass Unit Converter

Edit either side and the other follows. Convert freely between kilograms, grams, milligrams, pounds, ounces, stones, metric tonnes, Hong Kong jin (司馬斤) and tael (司馬兩) — handy for gym plate weights, US recipe imports, baggage allowance, wet-market 半斤豬肉, or pharmacy 三錢 (one-tenth of a tael).

From

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Formula

kilograms = value × factor[from] result = kilograms / factor[to] factor[lb] = 0.453 592 37 (1959 international avoirdupois pound) factor[jin] = 0.604 789 82 (HK Cap. 68 司馬斤) factor[tael] = factor[jin] / 16

· 1 lb = 0.453 592 37 kg exactly (1959 international yard-and-pound agreement); 1 kg ≈ 2.204 6 lb.
· 1 oz = 1/16 lb ≈ 28.349 5 g; 1 stone = 14 lb ≈ 6.350 3 kg (the British unit for body weight).
· 1 metric tonne (t) = 1 000 kg ≈ 2 204.62 lb (note: the US short ton is 2 000 lb and is not supported here).
· Hong Kong Cap. 68 (Weights and Measures Ordinance, Sch. 1) sets 1 catty (司馬斤) = 0.604 789 82 kg and 1 catty = 16 tael (司馬兩) — the "jin / tael" used in HK wet markets, Chinese-medicine shops and gold-shop jewellery.
· 1 tael ≈ 37.799 g ≈ 1.333 oz; 1 錢 (a Chinese-medicine sub-unit) = 1/10 tael ≈ 3.78 g.
· Mainland China has used 市斤 = 500 g since 1959, which is different from the Hong Kong 司馬斤 (≈ 605 g) — watch out when converting recipes from the Mainland.

Frequently asked

How heavy is 半斤豬肉 (half a jin of pork) from a Hong Kong wet market?

A Hong Kong jin (司馬斤) is about 605 g, so 半斤 is roughly 302 g (just under one-third of a kilogram). Mainland Chinese recipes use a different jin (市斤 = 500 g), where 半斤 means only 250 g — almost a fifth less.

I weigh 70 kg — what is that in pounds and stones?

70 kg × 2.2046 ≈ 154.32 lb. A stone is 14 lb, so that is ≈ 11 st 0.3 lb — the format British doctors and the NHS still use for body weight.

A Chinese-medicine prescription says 三錢 — how many grams is that?

A 錢 (qiān/tsin) in Hong Kong is 1/10 of a Chinese-medicine tael (司馬兩), so 1 錢 ≈ 3.7799 g and 三錢 ≈ 11.34 g. Type 0.3 tael into this tool to see the equivalent in grams.

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