Gold Purity & Impurity Calculator

Pro tips most people learn the hard way

• Zakat is calculated on PURE gold weight, not gross jewellery weight. For 10 tola of 22K, Zakat applies to 9.17 tola of actual gold — not the full 10. Get this wrong and you're either underpaying (spiritually problematic) or overpaying (financially unnecessary). This calculator's pure-gold output is your Zakat input.
• Hallmark cheat sheet for Pakistani gold: 916 = 22K (the South Asian wedding standard), 750 = 18K (Western premium standard), 585 = 14K (US mass market), 375 = 9K (UK legal minimum). No stamp at all on inherited pieces is suspicious — pre-1960s Indian/Pakistani gold often went unhallmarked but is usually still 22K because that's what jewellers worked in.
• 22K vs 18K isn't a quality contest, it's a use-case decision. 22K (91.67% gold) is the South Asian sweet spot for wedding/store-of-value jewellery — high purity, deep yellow, acceptable durability for occasional wear. 18K (75%) is the Western fine-jewellery standard — harder, better for daily-wear rings, less deep yellow.
• Higher karat = more gold per gram, but also softer. 24K is so soft you can dent it with a fingernail, which is why it's rarely used for jewellery and mostly for bullion bars. 22K bends with rough wear. 18K is durable enough for daily rings. 14K and below feel almost like everyday metal.
• Pro tip: for any purchase above PKR 500,000, get the piece tested with an XRF spectrometer before paying. Reputable jewellers will let you. Walking in with the stamp's claimed karat and confirming with a 30-second non-destructive scan saves you from paying 22K prices for unmarked 18K — a small but real Sarafa Bazar trick.