Most of the tools I bookmark are for photos and files. This one is for a different five-minute job: a broken chain or a 14k ring, and a shop that wants to buy it before you have a number of your own.
The price on a finance site is 24k bullion. Drawer jewelry is not. The stamp is a fraction of 24. 14k is about 58 percent gold. 18k is 75 percent. 9k is 37.5 percent. Melt value is weight × that fraction × today’s fine-gold price per gram. A pawn shop or scrap desk then pays a slice of melt. They still have to assay the piece and wait on a refiner. If you skip that step, every ticket looks random.
Two mistakes wreck the math. A kitchen-scale ounce is 28.35 grams. A troy ounce is 31.1. Use grams. Stones, steel posts, and watch straps add weight the stamp does not cover. Weigh the metal, not the whole object.
I write down grams and karat at home, then compare melt to the slip. For that second pass I keep a gold calculator bookmarked. Enter the weight and the stamp, read melt, then decide if the discount is ordinary or a walk-away number. No account. Browser only.
Coins and bars sit closer to the spot chart. Household jewelry is scrap unless a piece has collector value. One bookmark is enough for the check. The lighting in the shop is not.