Jewelry Making Calculators

Metal weights, alloys, wire, settings and stone pricing. 13 calculators for the bench.

Ring weight is the one that protects a quote. Metal is the dominant cost in most pieces, and weight scales with both ring size and profile in ways that estimating by eye does not capture. Going from a size 6 to a size 12 in the same band profile can add over 50% to the metal. Quoting a flat price across sizes means losing money on every large ring, and jewellers who do it usually only notice at stock-take.

Gold karat mixing works from fineness by weight, and the arithmetic catches people who reason in karats directly. 24k is pure, so 18k is 75% gold and 14k is 58.3%. Mixing equal weights of 18k and 14k gives about 16.7k, not 16k, and the difference is enough to fail an assay if you were aiming for a hallmark boundary.

Metal weights use actual densities, which is why the same ring costs different amounts in different metals beyond the price per gram. Platinum is roughly 60% denser than 14k gold, so an identical ring uses far more metal by weight, and that compounds a per-gram price that is already higher.