Weight Converter: Kg to Lbs, Ounces, Stone & 24 Units

A recipe written in ounces, a dumbbell labeled in pounds, a gold price quoted per tola, a shipping invoice billed by the tonne — and you, standing in the middle, trying to make them all speak the same language. That is exactly why we built the Tooliqo Weight & Mass Converter: one fast, free tool that translates between 24 weight and mass units instantly, in six languages, with the kind of accuracy you can take to a jeweler's counter or a chemistry exam. This guide is its companion. Below you will find the live converter itself, the exact weight conversion formula it runs on, quick-reference charts for the most searched conversions (kg to lbs, grams to ounces, stone to kg and more), and a plain-English tour of every unit family — metric, US and imperial, troy and jewelry weights, and the scientific oddballs like the slug and the dalton.

Try the Weight & Mass Converter

Type a value, pick your units, and watch the result update as you type. No buttons, no page reloads, no sign-up. The tool below is the full converter — the same one this whole article is about.

Weight Converter Embed Code for Your Website:

Weight is one of the most intimate measurements we encounter in our daily lives. It's in the ingredients we weigh for a favorite recipe, the packages we ship to loved ones, the progress we track on our fitness journeys, and the precious moments we measure in the lives of those we care for. Yet, weight speaks in many dialects - a gram tells a delicate story, a pound carries a different weight, and a kilogram speaks a language all its own. This tool was created to help everyone find common ground in the language of weight.

You can copy this code and embed it on your website, offering your visitors a warm, practical companion that simplifies how they think about weight and mass. Whether they're following a cherished recipe from another country, calculating shipping costs for their small business, tracking their health and fitness goals, or solving a science problem, this Weight Converter turns complex calculations into a simple, natural experience.

The Weight Converter is an elegantly simple, interactive tool that allows your website visitors to instantly convert between milligrams, grams, kilograms, ounces, pounds, and tons. Simply enter a value in any unit, and watch as all other units update in perfect harmony - transforming what could be a confusing mental exercise into a moment of effortless understanding.

This tool is essential for cooking and baking blogs, fitness and wellness websites, shipping and e-commerce platforms, scientific and educational resources, or any space where weight and mass play a meaningful role. It's more than a converter - it's a thoughtful bridge that connects people across different measurement traditions and ways of experiencing the physical world.

The code is available in six global languages to welcome visitors from every corner of the earth: English - Spanish - French - Arabic - Chinese - Hindi.

You can easily switch the converter language by changing the parameter in the URL: ?lang=en

Available languages: en - es - fr - ar - zh - hi

1- Isolated iFrame Code (Ideal for Articles and Pages):

If you're writing about culinary adventures, fitness journeys, scientific explorations, or everyday life hacks, this method allows you to embed the tool directly within your content. The isolated iframe ensures a clean, focused experience, so your readers can experiment with weight conversions alongside your stories - connecting the numbers to the real-world experiences that give measurement its meaning and purpose.

<iframe id="tq_weight_converter" src="https://tools.tooliqo.co/weight-converter/?lang=en" title="Tooliqo" loading="lazy" scrolling="no" style="width:100%;max-width:100%;height:525px;border:0;overflow:hidden;display:block;margin:0 auto;"></iframe>
<script>(function(){var i="tq_weight_converter",b="https://tools.tooliqo.co/weight-converter/",dl="en";function L(){try{var h=(document.documentElement.getAttribute("lang")||"").toLowerCase();var ok=["ar","en","fr","es","zh","hi"];for(var k=0;k<ok.length;k++){if(h.indexOf(ok[k])===0)return ok[k];}}catch(e){}return dl;}function R(){var f=document.getElementById(i);if(!f)return;var lg=L();if(lg){var want=b+"?lang="+lg;if((f.getAttribute("src")||"").indexOf("lang="+lg)===-1)f.setAttribute("src",want);}window.addEventListener("message",function(e){var d=e.data;if(!d||typeof d.tqHeight!=="number"||d.tqHeight<50)return;try{if(f.contentWindow&&e.source&&e.source!==f.contentWindow)return;}catch(x){}f.style.height=(d.tqHeight+20)+"px";},false);}if(document.readyState==="loading"){document.addEventListener("DOMContentLoaded",R);}else{R();}})();</script>

2- Flexible Script (Suitable for Sidebars and Templates):

This method is perfect for sidebars, footers, or widget areas where you want the tool to be always accessible. The converter loads smoothly and gracefully, becoming a trusted companion that helps your visitors navigate the world of weight - whether they're scaling a recipe to feed a crowd, calculating package weights for shipping, tracking their personal wellness goals, or simply satisfying their curiosity about how different units of weight relate to one another.

Just add these lines to your website's code, and the Weight Converter will appear instantly, ready to help. It's fully responsive by design, offering a flawless experience on desktops, tablets, and mobile phones alike.

<div class="tooliqo-tool" data-tool="weight-converter" data-lang="en"></div>
<script src="https://tools.tooliqo.co/embed.js" async></script>

Note: The Weight Converter works in real-time, instantly updating all units as your visitors type or adjust values. No page reloads needed - just a smooth, intuitive experience that makes weight feel less like a calculation and more like a connection. Because when we understand weight better, we appreciate the tangible world around us - from the food we prepare to the things we share with those we love.

How to use the converter (and the small features that make it fast)

The basics take three seconds: enter a number in the Weight value field, choose a From unit and a To unit, and read the result. But we spent most of our time on the details you only notice once you use a converter every day:

• It converts as you type. There is no Convert button because there does not need to be one. Change the number, the units, or the decimals setting and the result, the full sentence, and the rate line all update instantly.
• One-tap swap. The circular arrow button between the two unit menus flips the direction — kg to lbs becomes lbs to kg — and recalculates immediately. Converting back and forth stops being a chore.
• Copy the real number. The Copy button places the full-precision result on your clipboard (up to 12 significant digits), not the rounded display. Paste it straight into a spreadsheet, an invoice, or a lab report.
• Decimals, your way. Leave the setting on Auto for smart significant-digit formatting, or lock it to 2, 4, 6, or 8 decimal places when a form demands a fixed format.
• Keyboard shortcuts. With the value field focused, press ↑ / ↓ to step the value by 1, or hold Shift to step by 10. Clicking the field selects everything, so you can type over the old value without deleting it first.
• Type numbers the way you already write them. The parser understands 2,500 (thousands separator), 2,5 (decimal comma, common in French and Spanish), and even 1e3 scientific notation.
• Six languages, detected automatically. English, Arabic (with full right-to-left layout), French, Spanish, Chinese, and Hindi. The tool reads the page language first, then your browser settings, and remembers your manual choice for next time.
• Grouped unit menus. The 24 units are organized into four labeled groups — Metric, US & Imperial, Precious metals & gems, and Scientific — so you find the tola or the troy ounce without scrolling past nanograms.
• Private by design. Every calculation happens in your browser. Nothing you type is sent anywhere, which also makes it work instantly even on a slow connection.

The weight conversion formula behind every result

Most conversion errors online come from one design flaw: tools that store a giant grid of pre-rounded rates between every pair of units. Rounding errors pile up, and pairs the author forgot simply break. Our converter does it the way a metrologist would: every unit is defined by one exact factor — its value in grams — and every conversion is a single multiplication and division through that common anchor.

That is the entire secret. It means the tool never chains one rounded rate into another, and it means you can reproduce any result by hand. Let's do a few, using the exact factors from the reference table:

Worked example 1 — kilograms to pounds (body weight)

Worked example 2 — ounces to grams (baking)

Worked example 3 — tolas to troy ounces (gold)

Worked example 4 — short tons to kilograms (freight)

Worked example 5 — kilograms to stone (UK body weight)

90 kg in stone: 90 × 1,000 ÷ 6,350.29318 = 14.1725 st. British convention splits the remainder back into pounds: 0.1725 × 14 = 2.4, so 90 kg reads as 14 st 2.4 lb.

Quick weight conversion chart (the searches everyone makes)

Bookmark this section. These are the conversions people reach for most, all derived from the tool's own exact factors:

Mental math: converting weight in your head

You will not always have a converter open — at a market stall, mid conversation, halfway through a podcast quoting pounds. These are the approximation tricks we actually use, with an honest note on how far off each one runs. For anything involving money, medicine, or contracts, come back to the tool; for everything else, these are close enough to sound like you know what you are talking about.

• Kilograms to pounds: double it, then add 10 percent. 75 kg → double is 150, plus 15 is 165 lb. True answer: 165.35 lb. This trick stays within a quarter of a percent, which is why it is the one worth memorizing.
• Pounds to kilograms: halve it, then knock 10 percent off. 165 lb → half is 82.5, minus 8.25 is about 74 kg (true: 74.8 kg). Slightly rougher in this direction; dividing by 2.2 is better if you can manage it.
• Ounces to grams: multiply by 30, then trim 5 percent. 8 oz → 240 minus 12 is 228 g (true: 226.8 g). For kitchen work, "an ounce is about 28 g" also serves.
• Stone to kilograms: times six, plus a third of the stones. 12 st → 72 plus 4 is 76 kg (true: 76.2 kg). Works because 6.35 is almost exactly six-and-a-third.
• Tonnes to US short tons: add 10 percent. 50 tonnes is about 55 short tons (true: 55.1). Going the other way, subtract 9 percent.
• Troy ounces to grams: call it 31. Within a third of a percent of the true 31.1035 g — good enough to sanity-check a gold quote, never good enough to settle one.

Exact multipliers cheat sheet

When you need the real rate rather than the party trick, these are the multipliers the converter itself uses — each derived from the exact gram factors in the big table. Values marked with a star are exact by definition; the rest are correctly rounded (never truncated) from those exact factors.

All 24 units in one reference table (exact values in grams)

This is the converter's actual internal table — the same numbers the tool multiplies and divides. Where a legal definition exists (the 1959 international pound, the metric carat, the SI prefixes), the value is exact, not approximate.

The metric family: from nanograms to tonnes

The metric side of the table is the easy one, and that is exactly the point. Since the French Revolution's metrologists tied everything to powers of ten, converting metric mass units is just moving a decimal point: 1 kg = 1,000 g = 1,000,000 mg. The tool handles seven rungs of that ladder, from the nanogram (a billionth of a gram, the territory of DNA samples and drug traces) up to the metric ton, the tonne, which moves the world's grain, steel, and cargo containers.

Two members of the family deserve a note. The quintal (100 kg) barely appears in English-speaking countries but is alive and well in agricultural markets across India, North Africa, and parts of Europe — wheat, olives, and sugar are still quoted per quintal in many trade bulletins. And the kilogram itself carries a quiet piece of modern history: until 2019 it was the last SI unit still defined by a physical object, a platinum-iridium cylinder in a vault near Paris nicknamed Le Grand K. Scientists noticed the prototype was drifting by micrograms relative to its copies — the world's reference for mass was, absurdly, changing mass — so the definition was rebuilt on the Planck constant, a number woven into physics itself. Your bathroom scale did not notice, but the kilogram you convert today is defined by the universe, not by a lump of metal.

Practical habit worth stealing: when a metric conversion result looks off by a factor of exactly 10, 100, or 1,000, you almost certainly picked the neighboring prefix (mg instead of g, quintal instead of kg). The grouped menus in the converter exist precisely to make that slip harder.

US and imperial weights: pounds, ounces, stones, and three different tons

Here is where conversion stops being decimal-point arithmetic and starts being history. The avoirdupois system — the everyday pound-and-ounce system of the United States and, in daily life, much of Britain — is built on the number 16: a pound is 16 ounces, an ounce is 16 drams. Underneath it all sits the grain, originally the weight of a single barleycorn taken from the middle of the ear. Seven thousand grains make a pound, and remarkably, the grain is still a working unit today: bullet and arrow weights, and some medication strengths, are quoted in grains.

The modern anchor is surprisingly recent. In the 1959 International Yard and Pound Agreement, six English-speaking nations fixed the pound at exactly 453.59237 grams — not measured, but defined. Every avoirdupois value in our table cascades from that single number, which is why the converter can state them exactly rather than approximately.

Why are there three different tons?

Because two countries counted their hundredweights differently. A ton was always 20 hundredweight — but Britain's hundredweight is 112 lb (eight stone), while America's is a round 100 lb. Twenty of each gives the long ton (2,240 lb ≈ 1,016 kg) and the short ton (2,000 lb ≈ 907 kg). Then the metric system arrived with the tonne (1,000 kg ≈ 2,205 lb), close enough to both to be dangerous. The three differ by up to 12 percent, which on a bulk cargo contract is not a rounding error, it is a lawsuit. When a document just says "ton," the country of origin usually tells you which one is meant; the converter carries all three so you never have to guess twice.

The stone: Britain's body-weight unit

Ask a British person their weight and you will hear something like "12 stone 6." The stone — 14 pounds, 6.35029 kg — was once a whole family of trade weights (a stone of wool differed from a stone of glass) until an 1835 act settled it at 14 lb. Today it survives almost exclusively for body weight in the UK and Ireland, which is why gym programs, boxing weigh-ins, and doctor's notes from Britain keep sending the rest of the world to a stone-to-kg converter.

Gold and jewelry weights: troy ounce, tola, mithqal, pennyweight, carat

Precious metals never adopted the everyday ounce, and the gap between the two systems has probably caused more expensive mistakes than any other pair of units. The troy ounce — named for the medieval trade fairs of Troyes, France — weighs 31.1034768 g, almost 10 percent more than the kitchen ounce's 28.3495 g. Every gold and silver spot price you have ever seen quoted is per troy ounce. A troy pound is 12 troy ounces (not 16), and each troy ounce splits into 20 pennyweight (dwt) of 24 grains each — the unit jewelers and scrap-gold buyers still use at the counter, because pricing per dwt makes small pieces easy to value.

Travel east and the reference units change. Across India, Pakistan, and much of the Gulf's gold souks, the tola rules: standardized under British India at 180 grains, which works out to 11.6638038 g — exactly three-eighths of a troy ounce. That clean ratio is why bullion in the region is cast as "ten-tola bars" (3.75 troy oz), a format so established that international refiners produce it specifically for South Asian markets. If you inherit gold measured in tolas and need to compare it with a spot price per troy ounce, the conversion is one tap in the tool — and thanks to the exact 3/8 ratio, the numbers close perfectly.

The mithqal is older still. It was the weight standard of the classical Islamic gold dinar, and the value carried through fourteen centuries of jurisprudence is 4.25 grams. It remains a living unit for one very practical reason: the zakat threshold (nisab) for gold is 20 mithqal, i.e. 85 grams of pure gold. If you are calculating zakat, weigh your gold in grams, divide by 4.25, and compare with 20 — or let the converter's mithqal unit do it directly. (For the full zakat calculation itself, our dedicated zakat tool on Tooliqo handles rates and thresholds.)

Finally, gemstones: the carat descends from the carob seed, once used as a counterweight on gem scales because the seeds were believed to be unusually uniform. The romance ended in 1907 when the metric carat was fixed at exactly 0.2 g (200 mg), subdivided into 100 "points" — a 50-point diamond is half a carat, 0.1 g. One thing the carat is not: a measure of gold purity. That is the karat (24k, 18k), a completely different concept that merely shares the sound. The converter deals in the mass carat; the purity karat is a percentage, not a weight.

The scientific outliers: the slug and the dalton

Two units in the tool exist mainly for students, engineers, and the incurably curious — and they bracket the entire scale of the table.

The slug answers a question most people never think to ask: if the pound is used as a force in engineering (pounds-force), what is the imperial unit of mass? The answer is the slug: the mass that accelerates at 1 ft/s² when pushed by one pound-force, equal to 14.5939 kg (32.174 lb). American aerospace and mechanical engineering courses still run on it, and unit confusion in exactly this territory — force versus mass in imperial units — is the classic cautionary tale of engineering classes, most famously the 1999 loss of NASA's Mars Climate Orbiter to a metric/imperial mix-up between teams.

At the opposite end sits the atomic mass unit, or dalton: one-twelfth of a carbon-12 atom's mass, 1.66053906892 × 10^-24 g. It is how chemists weigh molecules — water is about 18 daltons, a hemoglobin protein around 64,000. Feed the converter 1 gram to daltons and it returns 6.022141 × 10²³: Avogadro's number, the bridge between the atomic world and the gram in your hand. We included the dalton partly for chemistry homework and partly because a converter that can span 30 orders of magnitude — from a single atom to a freight tonne — without breaking is a converter you can trust in the middle of that range too.

Weight vs. mass: the difference, in one honest minute

Strictly speaking, this tool — like every "weight converter" — converts mass. Mass is the amount of matter in an object and never changes; weight is the force gravity exerts on that mass (weight = mass × g), and it changes with where you are standing. Your 75 kg of mass is 75 kg on the Moon too, but you would weigh only about one-sixth as much there. Even on Earth, gravity varies just enough that a precision scale calibrated in Oslo reads a hair differently in Nairobi.

So why does everyone say "weight"? Because in daily life on Earth's surface the two move together, bathroom scales are calibrated to display mass units, and centuries of trade language settled on "weight" long before physics separated the concepts. We follow the everyday convention in the tool's name and this article — kilograms, pounds, and stones as people actually use them — while the math underneath is proper mass conversion, which is exactly why units like the slug and the dalton can sit in the same menu.

Where weight conversion shows up in real life

Cooking and baking

American recipes speak in ounces and pounds; European and Middle Eastern ones in grams. Baking is chemistry, and swapping 8 oz for "roughly 250 g" instead of the true 226.8 g will change a dough. Convert once, write it on the recipe, and your scale does the rest.

Fitness and health

Gym plates in pounds, medical records in kilograms, British target weights in stone. Tracking progress across systems only works if the conversion is consistent — 2.20462, not "about 2.2" — especially when the goal is measured in fractions of a kilo per week.

Shipping, freight, and e-commerce

Carriers bill by weight brackets, customs forms demand kilograms, US suppliers quote short tons, and ocean freight sometimes still speaks in long tons. The three-ton trap in this article has a line item with your name on it if you guess.

Gold, silver, and jewelry

Spot prices per troy ounce, family gold in tolas, zakat thresholds in mithqals and grams, scrap offers per pennyweight. This is the one domain where a 10 percent unit error is money lost the same afternoon, which is why the tool gives the precious-metal units their own labeled group.

School, labs, and pharmacies

Milligram-to-gram slips are the classic dosage and chemistry-class error; grains still appear on some medication labels; physics problems switch between kilograms and slugs to keep students honest. A converter that shows the exact rate line ("1 gr = 64.79891 mg") doubles as a way to learn the relationships, not just consume them.

Six weight conversion mistakes that actually cost people

1. Treating "ton" as one unit. Metric tonne (1,000 kg), US short ton (907.185 kg), UK long ton (1,016.05 kg). Up to 12 percent apart. Always identify the country before you convert the cargo.

2. Pricing gold with the kitchen ounce. A troy ounce is 31.1035 g; a regular ounce is 28.3495 g. Value a gold coin with the wrong one and you are off by 9.7 percent — on today's gold prices, a painful number per coin.

3. Rounding 2.2 when precision matters. Fine for estimating luggage; wrong for dosing, freight billing, or lab work. The exact rate is 2.2046226218 lb/kg, and the 0.2 percent gap compounds over big weights. The tool's Copy button exists so the full-precision number travels with you.

4. Confusing carat with karat. Carat = gemstone mass (0.2 g). Karat = gold purity fraction (18k = 75 percent gold). A "1-carat 18k ring" uses both words correctly — and neither converts into the other.

5. Mixing decimal commas and thousands commas. "1,5" is one-and-a-half in Paris and fifteen hundred (mistyped) in New York. The converter parses both conventions sensibly, but when sharing numbers across borders, write the unit and be explicit: 1.5 kg.

6. Forgetting that pounds can mean force. In engineering contexts, "pound" sometimes means pound-force, whose matching mass unit is the slug. If a physics answer is off by a factor of 32.174, this is why.

Why we built this converter the way we did

There are a thousand weight converters online. Here is what makes this one worth bookmarking, stated plainly:

• Exact, sourced factors. Every unit is anchored to its legal or internationally agreed definition — the 1959 pound, the 1907 metric carat, the CODATA value of the dalton — and published in the table above so you can audit us.
• One-anchor math. A single multiplication and division through grams for every one of the 552 possible unit pairs. No pre-rounded rate grids, no chained errors, no missing pairs.
• Honest formatting. Auto mode shows up to 12 significant digits and switches to scientific notation only when a number would otherwise be unreadable. What you copy is the real value, not the pretty one.
• Genuinely multilingual. Full interfaces in English, Arabic (RTL), French, Spanish, Chinese, and Hindi — unit names included, not just button labels.
• Fast, free, and private. No account, no ads chasing you, no data leaving your browser. It loads once and works offline-fast from there.

It also has siblings: if this page earned its bookmark, the distance & length converter and the volume converter follow the same exact-factor philosophy.

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Weight conversion FAQ

The takeaway

Weight units are history you can hold: barleycorns and carob seeds, medieval French fairs and a retired platinum cylinder outside Paris, British hundredweights arguing with American ones, and a gold trade that still counts in tolas and mithqals. Converting between them does not require memorizing any of it — just one exact factor per unit and one honest formula, which is precisely what the Tooliqo Weight & Mass Converter puts in your pocket. Scroll back up, type a number, and let the tool speak all 24 dialects of heavy for you. If it saves you a mispriced ounce or a mis-billed tonne even once, it has done its job — and if you spot a unit we should add, tell us. This page, like the tool, is built to be used.