Methodology & data source

This page explains where the prices on GoldToPrice come from, how often they update and exactly how we turn a wholesale spot quote into a price per gram, per karat or per local currency.

Data source

All live and historical precious-metal prices are provided by MetalflowAPI, a market-data service that aggregates wholesale spot quotes for gold, silver, platinum and palladium. Prices are quoted per troy ounce of fine metal in USD, EUR, GBP and other currencies. Exchange rates for additional country currencies come from a public daily FX reference feed.

Update frequency

Spot prices are fetched from the data provider and cached on our servers for five minutes so the site stays fast. Open pages refresh live prices about every 60 seconds, short-range charts every minute and long-range history every few minutes. Historical responses are cached for fifteen minutes and FX responses for ten minutes; the upstream FX source publishes daily reference updates. A refresh can serve a stale cached observation immediately, so the displayed quote timestamp—not the page refresh time—indicates freshness.

Weight conversion

Precious metals are priced per troy ounce, which equals 31.1034768 grams. Price per gram = spot price per ounce ÷ 31.1035. Price per kilogram = price per gram × 1,000. Traditional units use: tola = 11.6638 g, Hong Kong tael = 37.429 g, Thai baht = 15.244 g, pennyweight = 1.555 g.

Karat purity maths

Spot prices refer to pure (24K) metal. For lower karats we multiply by the purity factor: karat price = 24K price × fineness. The factors we use are:

24K — nominal factor 0.999 (99.90%)
22K — nominal factor 0.9167 (91.67%)
21K — nominal factor 0.875 (87.50%)
20K — nominal factor 0.8333 (83.33%)
18K — nominal factor 0.75 (75.00%)
14K — nominal factor 0.5833 (58.33%)
12K — nominal factor 0.5 (50.00%)
10K — nominal factor 0.4167 (41.67%)
9K — nominal factor 0.375 (37.50%)

Example: an 18K item of 10 g contains 10 × 0.75 = 7.5 g of pure gold; its melt value is 7.5 × the price per gram of pure gold. The scrap gold calculator applies this formula automatically.

Hallmarks versus nominal factors

Nominal karat fractions and millesimal hallmarks are not always identical. 14K uses 0.5833 here, whereas 585 states 0.585. 22K uses 0.9167, whereas 916 states 0.916. 24K uses 0.999 for gross-weight jewelry estimates. Use an authoritative product fine-content specification or accepted assay for a settlement; do not apply purity twice to a mint's already-stated fine-gold weight.

Historical coverage and editorial standards

The archive depends on observations actually supplied for each metal and currency. Long series are sampled to a maximum of 600 points for a fast page; this means observed averages and extremes are not official full-series daily benchmarks. Missing dates and prices are never invented. Guides explain calculations and link to source authorities. GoldToPrice is the publishing organization; no individual expert credential or independent editorial review is claimed.

Disclaimer

Prices shown are indicative wholesale spot rates for information only. They do not include dealer premiums, refining charges, taxes or shipping, and may differ from quotes you receive. Nothing on this site is financial advice. Questions or corrections? Contact us.