Convert stones to avoirdupois ounces, or enter stones plus extra pounds and ounces without making a decimal-stone step.
Table of contents
How to use our Stones to Ounces Converter
- Choose What are you entering? based on your value: Decimal stones for values like 2.5 st, or Stones, pounds, and ounces for values like 10 st 7 lb 4 oz.
- If you chose Decimal stones, enter the amount in Stones (st).
- If you chose Stones, pounds, and ounces, enter Whole stones (st), Extra pounds (lb), and Extra ounces (oz).
- Set Answer decimal places if you want fewer or more digits shown, then select Calculate.
- Sanity-check Ounces by using Same weight in pounds: pounds times 16 should match the ounce answer after rounding.
Definitions
Stone (st): A weight unit equal to 14 pounds, so 1 stone equals 224 ounces.
Pound (lb): A common weight unit; this converter uses 16 ounces per pound.
Avoirdupois ounce (oz): The everyday weight ounce used with pounds in US customary and imperial weight systems, not a fluid ounce or troy ounce [1].
Decimal stones: A stone value written as one number, such as 2.5 st.
Mixed entry: A weight written with separate stone, pound, and ounce parts, such as 10 st 7 lb 4 oz.
Answer decimal places: The number of digits shown after the decimal point in the ounce answer.
Common mistakes and quick fixes
Mistake: Entering 10 st 7 lb as 10.7 in Stones (st).
Fix: Choose Stones, pounds, and ounces, then put 10 in Whole stones (st) and 7 in Extra pounds (lb).
Mistake: Putting 14 or more in Extra pounds (lb).
Fix: Add each 14 lb to Whole stones (st), then leave only the leftover pounds in Extra pounds (lb).
Mistake: Putting 16 or more in Extra ounces (oz).
Fix: Add each 16 oz to Extra pounds (lb), then leave only the leftover ounces in Extra ounces (oz).
Mistake: Leaving Answer decimal places blank or using a number outside 0 to 6.
Fix: Enter a whole number from 0 to 6, such as 2 for hundredths of an ounce.
Mistake: Reading Ounces as fluid ounces.
Fix: Use Ounces only as weight ounces; this converter uses avoirdupois weight ounces, not liquid volume.
Limitations & Key Assumptions / Boundary Conditions
- This converter is for nonnegative weight amounts only.
- It uses avoirdupois weight ounces, not fluid ounces for volume and not troy ounces for precious metals.
- In mixed entry, Extra pounds (lb) must be less than 14 and Extra ounces (oz) must be less than 16 so each part stays in its normal range.
- Answer decimal places changes only the displayed rounding. The conversion math uses the full entered value.
- If a tiny positive value rounds to 0 at your chosen precision, the exact value is greater than zero but smaller than the displayed place value.
- This page does not convert to kilograms or grams; it only converts stones, pounds, and ounces within the same weight system.
Methodology
Conversion factors used
The converter uses 1 stone = 14 pounds and 1 pound = 16 avoirdupois ounces, so 1 stone = 224 ounces.
Decimal-stone entry
When What are you entering? is Decimal stones, the converter reads Stones (st) and multiplies by 224.
total_ounces = stones_decimal * 224
Stones, pounds, and ounces entry
When What are you entering? is Stones, pounds, and ounces, the converter changes each part to ounces, then adds the parts.
total_ounces = whole_stones * 224 + extra_pounds * 16 + extra_ounces
Check outputs
Same weight in pounds divides the ounce total by 16.
pounds_equivalent = total_ounces / 16
Same weight in decimal stones divides the ounce total by 224.
stones_decimal_equivalent = total_ounces / 224
Mini-example
For 11 st 3 lb 8 oz, the ounce total is 11 * 224 + 3 * 16 + 8 = 2520 oz. The same weight in pounds is 2520 / 16 = 157.5 lb, and the same weight in decimal stones is 2520 / 224 = 11.25 st.