How Many Ounces in a Pound

Ask anyone and they'll say 16. They're right — for flour, for a parcel, for a newborn on the midwife's scale. They're wrong for a gold bar. Precious metals are weighed on a different system altogether, one where a pound holds just 12 ounces. Two measuring traditions, the same two English words, and a gap wide enough that people buying silver online still get caught by it.

So the honest answer is: it depends what you're weighing. For everyday goods the unit is the avoirdupois pound — 16 ounces. For gold, silver and platinum it's the troy pound — 12 troy ounces. The converter below switches between the two so you can see the difference directly.

The everyday answer: 16 ounces

Avoirdupois is the system behind nearly every weight you meet — supermarket scales, postage, the bathroom scale. One pound is 16 ounces, flat. Since 1959 it has had an exact metric definition: the international yard-and-pound agreement, signed by the US, UK, Australia, Canada, New Zealand and South Africa, fixed the pound at precisely 0.45359237 kilograms. Divide by 16 and an avoirdupois ounce is exactly 28.349523125 grams.

Why 16 and not 10? Because 16 is a half, halved, halved, and halved again. On a balance scale you can split a pound into 8 ounces, then 4, then 2, then 1, without ever reaching for a fraction — a real practical virtue back when your "calculator" was a beam and a box of weights. Ten would not divide nearly so cleanly.

The precious-metals answer: 12 ounces

Gold, silver, platinum and gemstones are weighed in the troy system, and a troy pound contains only 12 troy ounces. Here is the part that catches people out: a troy ounce is heavier than an everyday ounce — 31.103 grams against 28.350 — yet a troy pound is lighter than an everyday pound, 373.24 grams against 453.59. Fewer ounces, each one heavier, and the total still comes out smaller.

That is exactly the trap behind a recurring argument among silver buyers. Someone weighs out "a pound" of silver expecting 16 ounces and the numbers refuse to line up. They refuse because precious-metal weight is troy: it takes roughly 14.58 troy ounces to equal one everyday avoirdupois pound, and a troy pound is a third figure again. The spot price of gold you see quoted is always per troy ounce — never the ounce on your kitchen scale.

Where the strange word comes from

Avoirdupois is not a misspelling. It is Old French — aveir de peis, "goods of weight" — and it named the system used to weigh bulk merchandise. Troy most likely points to Troyes, a medieval French trade-fair town. Both systems are centuries old, and for a long stretch England ran several competing pounds side by side — a merchant's pound, a tower pound, a London pound — before avoirdupois won out for general use and troy was kept on for the mint and the bullion trade.

The ounce that measures nothing solid

One more ounce muddies the search results: the fluid ounce, which measures volume, not weight, and has no fixed relationship to either pound. It is not one-sixteenth of anything you can hold. Worse, the US fluid ounce and the UK fluid ounce are different sizes. If a recipe or a bottle says "fl oz", set the pound aside entirely — that ounce belongs to a different question.

Printable conversion chart

The full chart below converts every ounce up to a pound. Tick the options and tap print to save a clean, branded PDF for the kitchen wall or the workshop.

Sources

• The international yard and pound agreement (1959) — defines the avoirdupois pound as exactly 0.45359237 kg; figures as published by NIST
• The troy ounce of 31.1034768 g and the 12-ounce troy pound — standard bullion-trade and Royal Mint references
• Avoirdupois and troy etymologies — Oxford English Dictionary entries [VERIFY exact wording before publication]
• Wikipedia, "Avoirdupois" — general corroboration of the dual-system history

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