One stone equals 14 pounds, or 6.35029318 kilograms, in US/UK avoirdupois weight.
Curious about the classic British unit? Here’s the short version: in everyday weight, a stone maps cleanly to pounds with no tricks. The math is simple, and the conversions below let you work fast on forms or during weigh-ins.
What The Stone Unit Means
The stone is a longstanding imperial unit used in the UK and Ireland, mainly for body weight. In modern usage it pairs with pounds, and many people still give their weight in the format “st lb.” While retail trade moved to metric, the measure lives on in daily speech, sport, and medical notes.
Authoritative references align on the factor: one stone equals fourteen avoirdupois pounds. That pairing reflects the same pound used on scales across the US and UK today, which is fixed to the kilogram. You’ll see the exact kilogram link in the source from NIST below.
Stone To Pounds Conversion Formula
The rule is direct: pounds = stones × 14. To go the other way, divide by 14. For metric, multiply stones by 6.35029318 to get kilograms, since one pound equals exactly 0.45359237 kg and a stone holds fourteen of those.
Tip: keep 6.35 in your head for quick mental work. For medical charting or gear specs, use the full 6.35029318 factor for precise results.
Broad Reference Table: Stones, Pounds, And Kilograms
| Stones | Pounds | Kilograms |
|---|---|---|
| 0.5 | 7.0 | 3.17515 |
| 1.0 | 14.0 | 6.35029 |
| 1.5 | 21.0 | 9.52544 |
| 2.0 | 28.0 | 12.70059 |
| 2.5 | 35.0 | 15.87578 |
| 3.0 | 42.0 | 19.05093 |
| 3.5 | 49.0 | 22.22608 |
| 4.0 | 56.0 | 25.40118 |
| 4.5 | 63.0 | 28.57633 |
| 5.0 | 70.0 | 31.75148 |
| 5.5 | 77.0 | 34.92663 |
| 6.0 | 84.0 | 38.10177 |
| 6.5 | 91.0 | 41.27692 |
| 7.0 | 98.0 | 44.45207 |
| 7.5 | 105.0 | 47.62722 |
| 8.0 | 112.0 | 50.80235 |
| 8.5 | 119.0 | 53.97750 |
| 9.0 | 126.0 | 57.15265 |
| 9.5 | 133.0 | 60.32779 |
| 10.0 | 140.0 | 63.50293 |
| 10.5 | 147.0 | 66.67808 |
| 11.0 | 154.0 | 69.85323 |
| 11.5 | 161.0 | 73.02838 |
| 12.0 | 168.0 | 76.20352 |
| 12.5 | 175.0 | 79.37867 |
| 13.0 | 182.0 | 82.55382 |
| 13.5 | 189.0 | 85.72897 |
| 14.0 | 196.0 | 88.90410 |
| 14.5 | 203.0 | 92.07925 |
| 15.0 | 210.0 | 95.25440 |
| 15.5 | 217.0 | 98.42955 |
| 16.0 | 224.0 | 101.60469 |
| 16.5 | 231.0 | 104.77984 |
| 17.0 | 238.0 | 107.95499 |
| 17.5 | 245.0 | 111.13014 |
| 18.0 | 252.0 | 114.30528 |
| 18.5 | 259.0 | 117.48043 |
| 19.0 | 266.0 | 120.65558 |
| 19.5 | 273.0 | 123.83073 |
| 20.0 | 280.0 | 127.00586 |
Convert Stone To Pounds Accurately
Use the factor of 14 for every case tied to everyday mass. That covers body weight, luggage, and gym plates. Beware of historic lists that mention other values for special goods; those were local rules from past centuries and do not apply to modern scales.
Quick Mental Math For Daily Use
Halves: add seven. Example: 8½ st is 8×14 + 7 = 119 lb.
Quarters: every quarter stone adds 3½ lb. So 12 st ¼ = 168 + 3½ = 171½ lb.
Round to 6.35 kg per stone: 9 st ≈ 57.2 kg; 11 st ≈ 69.9 kg. For forms that need one decimal place, this rounding works well.
Back to stones: split pounds by 14. Say 183 lb ÷ 14 = 13 remainder 1, so 13 st 1 lb. In decimals, 183 ÷ 14 ≈ 13.1 st.
Why People Still Use Stones
Sports broadcasts and fitness chats in the UK use stones because the step size feels human friendly. You can say “eleven and a half” and be understood at once. Doctors may record kilograms in systems yet speak stones and pounds with patients. Scales in gyms often show both, which keeps habits alive.
Retail labeling follows metric law, with imperial allowed as a secondary display in many cases. That is why you might see kg as the headline number on a packet while lb appears alongside in smaller type.
Common Pitfalls And How To Avoid Them
Mixing systems: a “pound” in this context is the everyday avoirdupois pound, not troy. Jewelry uses troy; body weight does not.
Copying old charts: older town rules listed stones of many sizes for wool, glass, or meat. Those values cause confusion when pulled into modern notes. Stick with the 14 lb definition for current everyday use.
Rounding too hard: shaving kilograms to one decimal is fine for fitness chat. For dosing or engineering, use full precision and the exact pound-to-kilogram link.
Everyday Mixes Of Stones And Pounds
The format “st lb” appears in clinics and sports pages. The table below converts common mixes to total pounds and kilograms. That way you can read any record at a glance or fill forms that ask for a single number.
| Stone + Pound | Total Pounds | Kilograms |
|---|---|---|
| 8 st 7 lb | 119 | 53.98 |
| 9 st 0 lb | 126 | 57.15 |
| 9 st 7 lb | 133 | 60.33 |
| 10 st 0 lb | 140 | 63.50 |
| 10 st 7 lb | 147 | 66.68 |
| 11 st 0 lb | 154 | 69.85 |
| 11 st 7 lb | 161 | 73.03 |
| 12 st 0 lb | 168 | 76.20 |
| 12 st 7 lb | 175 | 79.38 |
| 13 st 0 lb | 182 | 82.55 |
| 13 st 7 lb | 189 | 85.73 |
| 14 st 0 lb | 196 | 88.90 |
| 15 st 0 lb | 210 | 95.25 |
| 16 st 0 lb | 224 | 101.60 |
How To Convert On A Phone Or Paper
On paper: multiply stones by 14, then add any extra lb. To reach kg, multiply the pound total by 0.45359237.
On a phone: use a basic calculator. Enter stones, press ×14, then ×0.45359237 for kg. Save the factor in notes for repeat use.
In spreadsheets: set a cell to =A2*14 for pounds or =A2*6.35029318 for kilograms when A2 holds stones.
Small Reference You Can Save
• 1 st = 14 lb = 6.35029318 kg
• 7 lb = 0.5 st
• 1 lb = 0.45359237 kg
• 10 st = 140 lb = 63.5029318 kg
Bookmark this page or jot the four lines above in a notes app. With those, any everyday conversion becomes a two-step tap.
Credible Sources Behind The Numbers
The pound’s exact kilogram link comes from the US National Institute of Standards and Technology. The stone’s modern value as fourteen pounds is described by Britannica’s reference article. The UK’s guidance page explains why dual displays appear on retail packs.
See: NIST conversion tables and Britannica on the stone unit. For retail labeling context, see the UK guidance on markings and sales.
Worked Examples With Step-By-Step Math
Example 1: A clinic record shows 10 st 6 lb. Total pounds = 10×14 + 6 = 146 lb. Kilograms = 146×0.45359237 = 66.22 kg.
Example 2: A gym plate stack lists 3 st. That is 3×14 = 42 lb. In kilograms, 42×0.45359237 = 19.05 kg.
Example 3: A travel form asks for kg. Your weight is 12 st 9 lb. Total pounds = 12×14 + 9 = 177 lb. Kilograms = 177×0.45359237 = 80.29 kg.
Example 4: A fitness plan shows a target of 75 kg. Pounds = 75 ÷ 0.45359237 = 165.35 lb. In stones, 165.35 ÷ 14 = 11.81 st, which reads as 11 st 11 lb (rounding to the nearest pound).
Rounding And Precision That Work In Real Life
One decimal for kg: many forms accept one decimal; 69.9 kg is fine for 11 st using 6.35. For lab work or dosing, keep full digits.
Pounds to the nearest half: in coaching notes, halves keep numbers readable. A record like 154.5 lb is easy to map back to 11 st 0.5 lb.
Decimal stones in print: if a paper needs decimals, 10.5 st means ten and a half. Multiply 10.5×14 = 147 lb to verify.
Unit Abbreviations And Style
Writers often use “st” for stone, “lb” for pound, and “kg” for kilogram. Leave them lowercase and without periods. On first use in a document, spell the unit out once. After that, the short forms keep tables tidy.
When mixing formats, put stones first, pounds second: 13 st 4 lb. For metric, place the number then the unit with a space: 60 kg. In code and spreadsheets, keep the factors as constants to avoid drift.
Troubleshooting Mismatched Readings
Scale set to lb only: many bathroom scales can cycle through lb, kg, and st-lb. Tap the mode button until the display changes. If you only see lb, convert with the steps above.
Gym plates marked in kg: add the plates in kilograms, then divide by 0.45359237 to see the total in pounds. Split by 14 if you need a stones figure for a log.
Historic charts on a wall: if a poster lists odd stones for wool or meat, treat it as a museum piece. Modern mass uses the 14 lb figure.
Where This Unit Shows Up Today
Broadcasts still read out body weight in this format for boxing and mixed martial arts held in the UK or Ireland. Stadium signage and club materials may print both kg and st-lb for fans. Health apps with UK settings often let users pick stones with pounds as a sub-unit.
In retail, packs show grams and kilograms first, with pounds allowed as a secondary reading under UK rules. That keeps shoppers fluent in both systems while keeping the metric headline clear.
Handy Takeaways You Can Save
• A stone holds fourteen pounds. Multiply stones by 14 to reach pounds. Divide pounds by 14 to return to stones.
• For metric, one pound equals exactly 0.45359237 kg, so one stone equals 6.35029318 kg.
• Halves add seven pounds; quarters add three and a half. Those small steps make mental math quick during weigh-ins.
• When you spot conflicting charts from older trade rules, ignore them for daily health numbers. Use the modern figure shown above and the tables on this page.
• Keep a tiny card in your wallet or a note on your phone with the four lines in the small reference section, and you’ll be set anywhere.