What this calculator does
The Pounds and Ounces Calculator lets you add or subtract two weights expressed in pounds (lb) and ounces (oz). It is handy for postage, cooking, baby weights, shipping packages, and any time you need to combine imperial weights without juggling the 16-ounce conversion in your head.
How to use it
Choose Add or Subtract, then enter the first weight's pounds and ounces and the second weight's pounds and ounces. The calculator converts both values to total ounces, performs the operation, and converts the answer back into clean pounds and ounces. Subtraction never returns a negative result — it is clamped to zero.
The formula explained
Because one pound equals 16 ounces, any weight can be flattened to a single number of ounces: \(\text{total\_oz} = \text{lb} \times 16 + \text{oz}\). After adding or subtracting the two totals, the result is normalized: whole pounds are \(\lfloor \text{total\_oz} \div 16 \rfloor\) and the leftover ounces are \(\text{total\_oz} \bmod 16\).
Worked example
Add 5 lb 8 oz and 2 lb 12 oz. Weight 1 = $$5 \times 16 + 8 = 88 \text{ oz}.$$ Weight 2 = $$2 \times 16 + 12 = 44 \text{ oz}.$$ Total = 132 oz. Pounds = $$\lfloor 132 \div 16 \rfloor = 8,$$ ounces = $$132 - 8 \times 16 = 4.$$ The answer is 8 lb 4 oz.
FAQ
How many ounces are in a pound? There are exactly 16 ounces in one avoirdupois pound.
Can I enter fractional ounces? Yes — ounces accept decimals such as 4.5, and the result keeps up to two decimal places.
What if the subtraction is negative? The result is clamped to 0 lb 0 oz, since a negative physical weight is not meaningful here.
