International Gold Unit Converters — Every World Standard, One Tool
Gold trades under a half-dozen different weight standards depending on which market you are in: troy ounce in London/New York, gram across Europe, tola in South Asia, tael in Greater China, pennyweight in the US jewellery trade, and grain in historical or assay contexts. This global unit converter handles all of them on one screen — enter any quantity in any unit and see the equivalent value in every other.
It is the tool international bullion brokers, refinery intake desks, customs brokers, and cross-border traders use to reconcile transactions across markets. The internal conversion ladder is grams → everything (with troy oz = 31.1035 g, tola = 11.664 g, HK tael = 37.429 g, Chinese tael = 31.25 g, pennyweight = 1.5552 g, grain = 0.0648 g) so cross-unit conversions are always grounded in a single metric reference.
When to use this calculator
- Cross-market arbitrage — compare London (troy oz), Mumbai (tola), Hong Kong (HK tael) and Shanghai (Chinese tael) prices in one calculation.
- Import/export documentation — most customs forms require metric grams; trade contracts often specify the local unit.
- Refinery intake — scrap intake in any local unit, converted to troy ounces of pure gold for payout.
- International estate valuation — heir-distribution calculations across jewellery weighed in different cultural units.
Why Gold Uses Multiple Weight Standards
Gold's weight diversity reflects its role as a universal store of value across civilisations that developed their own measurement systems independently. The troy ounce emerged from medieval European fair-trade weights; the tola from South Asian Mughal monetary standards; the tael from Chinese bronze-age and Silk Road commerce; the pennyweight from Anglo-Saxon coinage; the grain from ancient Mediterranean cereal-seed calibration. Each system became entrenched through centuries of local commercial use and legal codification.
Modern financial globalisation has not eliminated these units — it has made fluency in all of them essential for international traders, NRI investors, cross-border customs brokers and multi-market bullion dealers. A Pakistani importer buying from a Swiss refinery priced per gram must receive payment in tola at the Karachi Sarafa rate; a Hong Kong dealer buying from a South Asian supplier in tola must revalue it at the CGSE per-HK-tael rate. Both need instant cross-unit conversion.
The gram, as the SI base unit, is the lowest-common-denominator conversion point — every other unit on this page is defined relative to grams. For any specific unit pair, the recommended approach is to convert through grams using the reference ratios in the table below. For dedicated single-direction conversion, the troy ounce to grams, grams to tola, and tael converters each handle their respective ranges.
Conversion reference table (all relative to grams)
1 troy oz = 31.1035 g · 1 tola = 11.664 g · 1 HK tael = 37.429 g · 1 Chinese tael = 31.25 g · 1 pennyweight = 1.5552 g · 1 grain = 0.0648 g · 1 masha = 0.972 g · 1 ratti = 0.1215 g · 1 kg = 1000 g · 1 troy pound = 12 troy oz = 373.242 g.
Step-by-step calculation
Example: 10 g of 22K gold → all units
- 1
Grams (input)
Starting unit
10.000 g
- 2
Convert to tola
tola = grams ÷ 11.664
10 ÷ 11.664 = 0.8573 tola (0t 10m 2.9r)
- 3
Convert to troy oz
troy oz = grams ÷ 31.1035
10 ÷ 31.1035 = 0.3215 troy oz
- 4
Convert to pennyweight
dwt = grams ÷ 1.5552
10 ÷ 1.5552 = 6.430 dwt
- 5
Pure gold at 22K
pure (g) = grams × (22 ÷ 24)
10 × 0.9167 = 9.167 g pure
Sample conversions
| Input | Result |
|---|---|
| 1 troy oz | 31.1035 g = 2.667 tola = 0.831 HK tael = 20 dwt |
| 1 kg | 32.151 troy oz = 85.734 tola = 26.717 HK tael |
| 1 tola | 11.664 g = 0.375 troy oz = 0.3117 HK tael = 7.5 dwt |
| 1 HK tael | 37.429 g = 1.203 troy oz = 3.208 tola |
| 1 Chinese tael | 31.250 g = 1.004 troy oz = 2.679 tola |
Quick Reference — All Units to Grams
| Unit | Grams |
|---|---|
| 1 grain | 0.0648 g |
| 1 ratti | 0.1215 g |
| 1 pennyweight | 1.5552 g |
| 1 masha | 0.9720 g |
| 1 tola | 11.664 g |
| 1 troy oz | 31.1035 g |
| 1 HK tael | 37.429 g |
| 1 Chinese tael | 31.250 g |
All values internationally standardised. HK tael: CGSE standard. Tola: British Indian Mints Act 1835.
Frequently asked questions
Which gold weight unit should I use for investment tracking?
Use grams for international comparison (universal SI unit, no rounding issues) and supplement with troy ounces for matching against the LBMA fix or COMEX futures. For South Asian portfolios, add tola. For Hong Kong or Taiwanese holdings, add HK tael. The global unit converter shows all simultaneously.
Is the troy ounce being replaced by the gram?
Slowly, in retail and customs contexts. But the LBMA London Gold Price (fixed twice daily since 1919) remains troy-ounce denominated, as do COMEX futures and most institutional contracts. The troy ounce is likely to remain the trading-floor unit for another generation.
What is the difference between a troy ounce and a regular (avoirdupois) ounce?
Troy ounce = 31.1035 g; avoirdupois ounce = 28.3495 g. The troy is about 10% heavier. In precious metals, "oz" always means troy unless explicitly stated otherwise. In groceries and everyday goods, "oz" means avoirdupois. Mixing them up on a gold transaction produces a 10% error.
Which countries use tola for gold and which use grams?
Tola is the retail standard in Pakistan, India, Nepal and Bangladesh. International and institutional gold trade worldwide uses grams and troy ounces. Dubai uses grams at DMCC level and both grams and tola at the Dubai Gold Souk retail level. Hong Kong and China use HK tael and Chinese tael respectively.
What unit does the LBMA use to set the gold price?
The LBMA Gold Price (the benchmark twice-daily fixing) is set in USD per troy ounce. Parallel fixings in EUR and GBP per troy ounce are also published. All major gold ETFs (GLD, IAU, SGOL), futures contracts and OTC swaps reference the troy ounce LBMA price.
Is there a direct conversion between tola and HK tael?
1 tola = 11.664 g. 1 HK tael = 37.429 g. Therefore 1 HK tael = 37.429 ÷ 11.664 = 3.208 tola; and 1 tola = 11.664 ÷ 37.429 = 0.3117 HK tael. There is no single-step historical conversion factor — both are defined relative to grams.
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