Skip to content

Weight Converter — kg, lbs, oz, g, Stone & 10 More Units

1 kg = 2.205 lbs · 1 oz = 28.35 g · 1 stone = 14 lbs. Convert weight between 13 units — metric, imperial & troy. Includes conversion tables, formulas & real-world references. Free, private, runs in your browser.

No Tracking Runs in Browser Free
Result
-
All conversion factors verified against NIST Handbook 44 and tested for roundtrip accuracy across all 13 supported units. — Go Tools Engineering Team · Mar 18, 2026

Weight Quick Reference — Key Numbers to Know

How Many Pounds in a Kilogram?

1 kg = 2.205 lbs This is based on the NIST definition where 1 lb = 453.59237 g exactly. For quick mental math, multiply kg by 2.2.

How Many Grams in an Ounce?

1 oz = 28.350 grams One avoirdupois ounce (the everyday ounce) equals 28.3495 grams. A troy ounce (precious metals) equals 31.1035 grams.

How Many Ounces in a Pound?

1 pound = 16 ounces One avoirdupois pound contains exactly 16 ounces. This is an exact definition in the US customary and British imperial systems.

How Many Pounds in a Stone?

1 stone = 14 pounds One stone equals exactly 14 pounds (6.35 kg). The stone is commonly used for body weight in the UK and Ireland.

How Many Grams in a Kilogram?

1 kg = 1,000 grams This is an exact definition in the metric system. Also: 1 kg = 1,000,000 mg = 1,000,000,000 mcg.

How Many Milligrams in a Gram?

1 g = 1,000 mg This is an exact metric definition. Also: 1 g = 1,000,000 mcg. Move the decimal 3 places to convert.

How Many Grams in a Pound?

1 lb = 453.592 grams Based on the NIST exact definition: 1 lb = 453.59237 g. For quick math, use 454 g per pound.

How Many Kilograms in a Stone?

1 stone = 6.350 kg One stone = 14 pounds = 6.35029 kg. Used for body weight in the UK and Ireland.

Weight Conversion Formulas with Worked Examples

Mathematical formulas for the most common weight conversions, with worked examples.

Kilograms to Pounds

pounds = kilograms × 2.2046226218

pounds ≈ kilograms × 2.2 (quick estimate)

70 kilograms →

  1. 70 × 2.2046226218
  2. = 154.324

= 154.324 pounds

Pounds to Kilograms

kilograms = pounds × 0.45359237

kilograms = pounds ÷ 2.2046

150 pounds →

  1. 150 × 0.45359237
  2. = 68.039

= 68.039 kilograms

Ounces to Grams

grams = ounces × 28.349523125

grams ≈ ounces × 28.35 (quick estimate)

8 ounces →

  1. 8 × 28.349523125
  2. = 226.796

= 226.796 grams

Grams to Ounces

ounces = grams ÷ 28.349523125

ounces ≈ grams ÷ 28 (quick estimate)

200 grams →

  1. 200 ÷ 28.349523125
  2. = 7.055

= 7.055 ounces

Stone to Kilograms

kilograms = stone × 6.35029318

12 stone →

  1. 12 × 6.35029318
  2. = 76.203

= 76.203 kilograms

Troy Ounces to Grams

grams = troy ounces × 31.1034768

5 troy ounces →

  1. 5 × 31.1034768
  2. = 155.517

= 155.517 grams

Milligrams to Grams

grams = milligrams ÷ 1000

move decimal 3 places left

500 milligrams →

  1. 500 ÷ 1000
  2. = 0.5

= 0.5 grams

Carats to Grams

grams = carats × 0.2

grams = carats ÷ 5

3 carats →

  1. 3 × 0.2
  2. = 0.6

= 0.6 grams

What Is a Weight & Mass Unit Converter?

A weight and mass unit converter is a tool that translates measurements between different units of mass. It bridges metric (micrograms, milligrams, grams, kilograms, metric tons), avoirdupois/imperial (ounces, pounds, stone, short tons, long tons), and specialty units (carats, troy ounces, grains).

The metric system defines mass through the kilogram, the SI base unit. One kilogram = 1,000 grams = 1,000,000 milligrams. The avoirdupois system, used in the US and UK for everyday commerce, defines 1 pound = 16 ounces = 453.59237 grams exactly. The stone (14 pounds) is still used for body weight in the UK.

Specialty units serve specific industries: the carat (0.2 grams) is the universal standard for gemstone weight; the troy ounce (31.1035 g) is the standard for precious metals trading; and the grain (64.79891 mg) is used in ballistics and pharmacy.

Three different 'tons' cause frequent confusion: the metric ton (1,000 kg), the US short ton (2,000 lbs / 907.2 kg), and the British long ton (2,240 lbs / 1,016 kg). This converter handles all three.

All conversions use the exact factors defined by NIST and are calculated entirely in your browser — no data is transmitted to any server.

Weight measurement conventions vary worldwide. The United States uses pounds and ounces for nearly everything — groceries, body weight, shipping. The United Kingdom uses a hybrid system: stone and pounds for body weight, but kilograms and grams in shops (by law since 2000). Continental Europe, East Asia, and most of the world use kilograms and grams exclusively. China uses the 斤 (jīn, 1 jīn = 500 g) as an informal everyday unit alongside kilograms. In the precious metals and gemstone industries, troy ounces and carats are universal regardless of country.

Need to convert other measurement types? Try our length converter for distance units, volume converter for liquid measurements, or temperature converter for °C, °F and Kelvin.

// Key weight conversion factors:
// 1 kg       = 1000 g
// 1 lb       = 453.59237 g (exact, by definition)
// 1 oz       = 28.349523125 g
// 1 stone    = 6350.29318 g (14 lbs)
// 1 troy oz  = 31.1034768 g
// 1 carat    = 0.2 g (exact)
// 1 grain    = 0.06479891 g

// JavaScript conversion examples:
const kgToLbs = (kg) => kg * 2.2046226218;
const ozToGrams = (oz) => oz * 28.349523125;
const stoneToKg = (st) => st * 6.35029318;

console.log(kgToLbs(70));      // 154.324
console.log(ozToGrams(8));     // 226.796
console.log(stoneToKg(11));    // 69.853

Key Features of This Weight Converter

13 Weight & Mass Units Supported

Convert between microgram, milligram, gram, kilogram, metric ton, ounce, pound, stone, short ton, long ton, carat, troy ounce, and grain.

Instant Real-Time Conversion

Results update as you type — no need to click a convert button. Change units and see the result immediately.

Grouped Unit Selector

Units are organized into Metric, Imperial, and Specialty groups for quick selection.

Metric, Avoirdupois & Troy Systems

Clearly separates everyday ounces (28.35 g) from troy ounces (31.10 g), and distinguishes metric tons, short tons, and long tons.

Industry-Specific Units

Includes carats for gemstones, troy ounces for precious metals, and grains for pharmacy and ballistics — the units professionals actually need.

100% Browser-Based & Private

All calculations happen locally in your browser. No server requests, no tracking, no data storage — your values never leave your device.

Weight Conversion Examples — kg, lbs, oz, Stone

Kilograms to Pounds — Body Weight

70
154.324 lb

One kilogram equals approximately 2.20462 pounds. A 70 kg person weighs about 154.3 pounds. This is the single most common weight conversion, used daily in fitness, healthcare, and travel between metric and imperial countries.

Ounces to Grams — Cooking & Nutrition

8
226.796 g

One avoirdupois ounce equals approximately 28.3495 grams. Eight ounces (half a pound) is about 226.8 grams. This conversion is essential when following recipes that mix US and metric measurements.

Stone to Kilograms — UK Body Weight

11
69.853 kg

One stone equals exactly 14 pounds or approximately 6.35029 kilograms. Eleven stone (154 lbs) is about 69.85 kg. The stone is still widely used for body weight in the UK and Ireland.

Carats to Grams — Gemstone Weight

2.5
0.5 g

One carat equals exactly 0.2 grams (200 milligrams). A 2.5 carat diamond weighs exactly 0.5 grams. The carat is the standard unit for gemstones and pearls, defined by international agreement since 1907.

Troy Ounces to Grams — Precious Metals

1
31.1035 g

One troy ounce equals approximately 31.1035 grams — about 10% heavier than a standard avoirdupois ounce (28.35 g). Gold, silver, and platinum are always quoted in troy ounces on commodity markets.

Pounds to Ounces — Shipping & Postage

3.5
56 oz

One pound contains exactly 16 ounces. A 3.5-pound package weighs 56 ounces. Postal services often require weight in ounces for accurate rate calculation, especially for packages near weight thresholds.

How to Convert kg to lbs, oz to g & More

Quick reference for the most popular weight and mass unit conversions between metric, avoirdupois, and specialty systems.

How to Convert Kilograms to Pounds

Kilogram (kg) → Pound (lb)

Multiply the number of kilograms by 2.20462 to get pounds. For example, 70 kg = 154.32 lbs. This is the most common weight conversion, used for body weight, luggage limits, and product labeling.

70 kg → 154.324 lb

For quick mental math, multiply kg by 2 and add 10%. Example: 80 kg → 160 + 16 = 176 lbs (exact: 176.37 lbs).

Try it above — enter your value and see the result instantly.

How to Convert Pounds to Kilograms

Pound (lb) → Kilogram (kg)

Divide the number of pounds by 2.20462, or multiply by 0.45359. For example, 150 lbs = 68.04 kg. Essential for converting US product weights to metric for international use.

150 lb → 68.039 kg

For a quick estimate, halve the pounds and subtract 10%. Example: 200 lbs → 100 - 10 = 90 kg (exact: 90.72 kg).

Try it above — enter your value and see the result instantly.

How to Convert Ounces to Grams

Ounce (oz) → Gram (g)

Multiply the number of ounces by 28.3495 to get grams. For example, 4 oz = 113.4 g. This conversion is commonly used in cooking, nutrition labels, and postal weight calculations.

4 oz → 113.398 g

For a quick estimate, multiply ounces by 28 — it is only 1.2% off from the exact factor.

Try it above — enter your value and see the result instantly.

How to Convert Grams to Ounces

Gram (g) → Ounce (oz)

Divide the number of grams by 28.3495 to get ounces. For example, 200 g = 7.055 oz. Used when converting metric recipe amounts to US measurements.

200 g → 7.055 oz

For a quick estimate, divide grams by 28. A 100 g chocolate bar is about 3.5 oz.

Try it above — enter your value and see the result instantly.

How to Convert Stone to Kilograms

Stone (st) → Kilogram (kg)

Multiply the number of stone by 6.35029 to get kilograms. For example, 12 stone = 76.2 kg. This conversion is commonly used when converting UK body weight to metric.

12 st → 76.204 kg

Each stone is 14 lbs or about 6.35 kg. For quick math, multiply stone by 6 and add half a stone's worth (3 kg) — close enough for body weight estimates.

Try it above — enter your value and see the result instantly.

How to Convert Kilograms to Stone

Kilogram (kg) → Stone (st)

Divide the number of kilograms by 6.35029 to get stone. For example, 80 kg = 12.6 stone. Useful for converting metric body weight to the format used in the UK and Ireland.

80 kg → 12.598 st

Divide kg by 6.35 for stone. To get stone and pounds: take the whole stone number, then convert the decimal remainder (× 14) to pounds.

Try it above — enter your value and see the result instantly.

How to Convert Milligrams to Grams

Milligram (mg) → Gram (g)

Divide milligrams by 1,000 to get grams. For example, 500 mg = 0.5 g. This is the most common conversion in pharmacy and nutrition — every supplement label and drug dosage uses mg.

500 mg → 0.5 g

Simply move the decimal point 3 places left. 250 mg = 0.250 g, 1500 mg = 1.5 g.

Try it above — enter your value and see the result instantly.

How to Convert Carats to Grams

Carat (ct) → Gram (g)

Multiply carats by 0.2 to get grams (or divide by 5). For example, 3 ct = 0.6 g. The carat is the universal unit for gemstone weight, defined exactly as 200 milligrams since 1907.

3 ct → 0.6 g

Dividing carats by 5 gives the same result — easier mental math for round numbers.

Try it above — enter your value and see the result instantly.

Weight Conversion Charts — kg↔lbs, oz↔g, Stone↔kg

Pre-calculated reference tables for the most common weight conversions. Bookmark this page for quick lookups.

Kilograms to Pounds Chart

Kilograms to pounds conversion table (1-100 kg)
KG LB
1 Bag of sugar NaN
2 NaN
3 NaN
4 NaN
5 Bowling ball NaN
6 NaN
7 NaN
8 NaN
9 NaN
10 NaN
11 NaN
12 NaN
13 NaN
14 NaN
15 NaN
16 NaN
17 NaN
18 NaN
19 NaN
20 NaN
25 NaN
30 NaN
35 NaN
40 NaN
45 NaN
50 NaN
55 NaN
60 NaN
65 NaN
70 Average adult (154 lbs) NaN
75 NaN
80 NaN
85 NaN
90 NaN
95 NaN
100 Large adult / heavy luggage NaN

Pounds to Kilograms Chart

Pounds to kilograms conversion table (1-200 lbs)
LB KG
1 Loaf of bread NaN
2 NaN
3 NaN
4 NaN
5 Bag of flour NaN
6 NaN
7 NaN
8 NaN
9 NaN
10 NaN
11 NaN
12 NaN
13 NaN
14 NaN
15 NaN
16 NaN
17 NaN
18 NaN
19 NaN
20 NaN
25 NaN
30 NaN
35 NaN
40 NaN
45 NaN
50 Airline checked bag limit NaN
55 NaN
60 NaN
65 NaN
70 NaN
75 NaN
80 NaN
85 NaN
90 NaN
95 NaN
100 Average 12-year-old NaN
105 NaN
110 NaN
115 NaN
120 NaN
125 NaN
130 NaN
135 NaN
140 NaN
145 NaN
150 Average adult (68 kg) NaN
155 NaN
160 NaN
165 NaN
170 NaN
175 NaN
180 NaN
185 NaN
190 NaN
195 NaN
200 NaN

Ounces to Grams Chart

Ounces to grams conversion table (1-32 oz)
OZ G
1 Slice of bread NaN
2 NaN
3 NaN
4 NaN
5 NaN
6 Baseball NaN
7 NaN
8 Half pound (227 g) NaN
9 NaN
10 NaN
11 NaN
12 Soda can NaN
13 NaN
14 NaN
15 NaN
16 One pound (454 g) NaN
18 NaN
20 NaN
22 NaN
24 NaN
26 NaN
28 NaN
30 NaN
32 NaN

Stone to Kilograms Chart

Stone to kilograms conversion table (6-25 stone)
ST KG
6 NaN
7 NaN
8 Small adult (51 kg / 112 lbs) NaN
9 NaN
10 NaN
11 Average adult (70 kg / 154 lbs) NaN
12 NaN
13 NaN
14 89 kg / 196 lbs NaN
15 NaN
16 Large adult (102 kg / 224 lbs) NaN
17 NaN
18 NaN
19 NaN
20 127 kg / 280 lbs NaN
21 NaN
22 NaN
23 NaN
24 NaN
25 NaN

Grams to Ounces Chart

Grams to ounces conversion table (10-500 g)
G OZ
10 NaN
20 NaN
30 NaN
40 NaN
50 Medium egg NaN
60 NaN
70 NaN
80 NaN
90 NaN
100 Standard chocolate bar NaN
125 NaN
150 NaN
175 NaN
200 Smartphone NaN
225 NaN
250 NaN
275 NaN
300 NaN
325 NaN
350 NaN
375 NaN
400 NaN
425 NaN
450 NaN
475 NaN
500 NaN

Milligrams to Grams Chart

Milligrams to grams conversion table (1–1000 mg)
MG G
1 NaN
2 NaN
3 NaN
4 NaN
5 Typical melatonin supplement NaN
6 NaN
7 NaN
8 NaN
9 NaN
10 NaN
25 NaN
50 NaN
75 NaN
100 NaN
200 Caffeine in a cup of coffee NaN
300 NaN
400 NaN
500 Vitamin C tablet NaN
600 NaN
700 NaN
800 NaN
900 NaN
1000 = 1 gram NaN

Carats to Grams Chart

Carats to grams conversion table (0.25–50 ct)
CT G
0.25 NaN
0.5 Typical engagement ring solitaire NaN
0.75 NaN
1 Most popular diamond size (0.2 g) NaN
1.25 NaN
1.5 NaN
1.75 NaN
2 NaN
2.25 NaN
2.5 NaN
2.75 NaN
3 NaN
3.25 NaN
3.5 NaN
3.75 NaN
4 NaN
4.25 NaN
4.5 NaN
4.75 NaN
5 NaN
10 NaN
20 NaN
30 NaN
40 NaN
50 NaN

How to Convert Weight Units Online

  1. 1

    Enter a Value

    Type or paste a numeric value into the input field. The tool accepts integers, decimals, and scientific notation.

  2. 2

    Select the Source Unit

    Choose the unit you are converting from using the 'From' dropdown. Units are organized by system: Metric, Imperial, and Specialty.

  3. 3

    Select the Target Unit

    Choose the unit you want to convert to using the 'To' dropdown. The result updates instantly as you change either unit.

  4. 4

    Copy or Swap

    Click the copy button to copy the result to your clipboard. Use the swap button to reverse the conversion direction instantly.

Common Weight Conversion Mistakes to Avoid

Confusing Mass and Weight Units

Mass (kg, g) measures the amount of matter. Weight (newtons) measures gravitational force. In everyday use they are interchangeable on Earth, but in scientific contexts the distinction matters.

✗ Wrong 
My weight is 70 kg (in a physics calculation)
✓ Correct 
My mass is 70 kg
My weight is 70 × 9.81 = 686.7 N

Confusing Troy Ounces and Avoirdupois Ounces

Troy ounces (31.10 g) are used for precious metals; standard ounces (28.35 g) are used for everything else. Mixing them up causes a 9.7% error in gold, silver, and platinum transactions.

✗ Wrong 
Gold price: $2,000/oz (using 28.35 g per oz)
✓ Correct 
Gold price: $2,000/troy oz (31.1035 g)
1 troy oz ≠ 1 avoirdupois oz

Confusing Metric Tons, Short Tons, and Long Tons

The three 'tons' differ by up to 12%. Using the wrong one in shipping or trade causes significant financial and logistical errors.

✗ Wrong 
Ship 5 tons of cargo (which ton?)
✓ Correct 
Ship 5 metric tons (5,000 kg)
or 5 short tons (4,536 kg)
or 5 long tons (5,080 kg)

Confusing Weight Ounces and Fluid Ounces

Ounces (oz) measure weight/mass. Fluid ounces (fl oz) measure volume. They are only approximately equal for water — for other substances the difference can be dramatic.

✗ Wrong 
8 oz of honey = 8 fl oz of honey
✓ Correct 
8 fl oz of honey ≈ 11.3 oz by weight
(honey is ~1.4× denser than water)

Confusing Net Weight and Gross Weight

Net weight is the product alone; gross weight includes packaging. In international trade, quoting the wrong one causes pricing and logistics errors. A '500 g' food package might have 530 g gross weight.

✗ Wrong 
Shipped 500 g of product (weighed with box)
✓ Correct 
Net weight: 500 g
Gross weight: 530 g (includes packaging)

Confusing Local Weight Units with Kilograms

Regional units like 斤 (jīn, China, 500 g) and livre (France, historically ~489.5 g) are often confused with kilograms. Mixing 斤 and kg doubles or halves the actual weight; confusing livre and pound introduces ~8% error.

✗ Wrong 
3 local units = 3 kg (wrong assumption)
✓ Correct 
1 jin (CN) = 500 g = 0.5 kg
1 livre (FR, historical) ≈ 489.5 g
1 pound (lb) = 453.6 g

When You Need Weight Conversion — 6 Scenarios

Fitness & Healthcare
Convert body weight between kilograms, pounds, and stone for fitness tracking, medical records, and BMI calculations across different measurement systems.
Shipping & Postage
Convert package weight between grams, kilograms, ounces, and pounds for accurate shipping rate calculations and postal compliance.
Cooking & Baking
Convert ingredient weights between grams, ounces, and pounds when following recipes from different countries or scaling portion sizes.
Jewelry & Gemstones
Convert between carats, grams, and troy ounces for gemstone evaluation, precious metal trading, and jewelry manufacturing.
Pharmacy & Medicine
Convert between micrograms, milligrams, grams, and grains for precise pharmaceutical dosage calculations and prescription formulations.
Science & Engineering
Convert between metric and imperial mass units for laboratory measurements, materials science, and engineering specifications.

Technical Details — NIST Factors & Precision

NIST-Defined Conversion Factors
Uses the exact conversion factors published by the National Institute of Standards and Technology: 1 lb = 453.59237 g (exact by definition), 1 troy oz = 31.1034768 g, 1 carat = 0.2 g (exact).
Double-Precision Arithmetic
Uses IEEE 754 double-precision floating-point numbers, providing at least 15 significant digits of precision for all conversions.
Client-Side Processing
All conversion logic runs in JavaScript within your browser. Zero network calls are made — the tool works fully offline once loaded.

Weight Conversion Best Practices — Avoid Costly Mistakes

Distinguish Troy from Avoirdupois
A troy ounce (31.10 g) is about 10% heavier than a standard ounce (28.35 g). Always verify which system is being used when dealing with precious metals versus everyday goods.
Specify the Type of Ton
A metric ton (1,000 kg), short ton (907.2 kg), and long ton (1,016 kg) differ by up to 12%. Always clarify which ton is meant in shipping, trade, and engineering contexts.
Use Grams for Cooking Precision
Volume measurements for ingredients can vary by 20-30% depending on packing. For precise baking and cooking, weigh ingredients in grams using a kitchen scale.
Know Your Audience's Unit System
When communicating weight internationally, always specify the unit explicitly. '150' could mean 150 lbs (68 kg, US), 150 kg (330 lbs, error), or 150 斤 (75 kg, China). In professional contexts, use SI units (kg/g) as the universal standard and provide local equivalents in parentheses.

Weight Conversion FAQ — 15 Common Questions

How many pounds are in a kilogram?
One kilogram equals approximately 2.20462 pounds. For quick mental math, multiply kilograms by 2.2 — this gives a result accurate to within 0.2%. For example, 80 kg × 2.2 = 176 lbs (exact: 176.37 lbs). The precise NIST conversion factor is 1 kg = 2.2046226218 lbs. To convert pounds back to kilograms, divide by 2.2046 or multiply by 0.4536.
How many grams are in an ounce?
One avoirdupois ounce equals approximately 28.3495 grams. For a quick estimate, use 28.35 grams per ounce. Common reference points: 1 oz = 28.35 g, 4 oz (quarter pound) = 113.4 g, 8 oz (half pound) = 226.8 g, 16 oz (one pound) = 453.6 g. Note that a troy ounce (used for precious metals) is heavier at 31.1035 grams.
How many pounds are in a stone?
One stone equals exactly 14 pounds (6.35029 kg). The stone is commonly used in the UK and Ireland for expressing body weight. Common stone-to-pound conversions: 8 stone = 112 lbs, 10 stone = 140 lbs, 12 stone = 168 lbs, 14 stone = 196 lbs, 16 stone = 224 lbs. To convert stone to kilograms, multiply by 6.35029.
What is the difference between a metric ton, a short ton, and a long ton?
A metric ton (tonne) = 1,000 kg = 2,204.6 lbs. A US short ton = 2,000 lbs = 907.2 kg. A British long ton = 2,240 lbs = 1,016 kg. The metric ton is used internationally, the short ton is standard in the US, and the long ton is used in British shipping. The differences are significant: a metric ton is about 10% heavier than a short ton, and a long ton is about 1.6% heavier than a metric ton.
What is the difference between mass and weight?
Mass is the amount of matter in an object, measured in kilograms. Weight is the force of gravity on that mass, measured in newtons. On Earth's surface, a 1 kg mass has a weight of approximately 9.81 newtons. In everyday use, 'weight' and 'mass' are used interchangeably because we almost always measure on Earth. This converter handles mass units — the values are correct anywhere on Earth's surface, though technically your 'weight' varies slightly with altitude and latitude.
What is the difference between a troy ounce and a regular (avoirdupois) ounce?
A troy ounce equals 31.1035 grams, while a standard avoirdupois ounce equals 28.3495 grams — the troy ounce is about 9.7% heavier. Troy ounces are exclusively used for precious metals (gold, silver, platinum, palladium). When a news report says 'gold is $2,000 per ounce,' it always means troy ounces. Confusing the two would cause a 9.7% pricing error.
How can I quickly convert kg to lbs in my head?
The easiest mental math method: multiply by 2 and add 10%. For example, 75 kg: 75 × 2 = 150, plus 10% (15) = 165 lbs (exact: 165.35 lbs). This gives accuracy within 0.2%. Another approach: multiply by 11 and divide by 5, which gives the exact factor of 2.2. For going from lbs to kg, divide by 2.2 — or halve the number and subtract 10%.
How accurate is this weight converter?
This converter uses the exact conversion factors defined by NIST (National Institute of Standards and Technology). All calculations use IEEE 754 double-precision floating-point arithmetic, providing at least 15 significant digits of precision. For everyday conversions, scientific calculations, and commercial transactions, the results are far more precise than any physical scale. The tool runs entirely in your browser with no rounding shortcuts.
Is my data safe when using this weight converter?
Yes, completely. All conversions are performed locally in your browser using JavaScript. No data is sent to any server — there are no network requests, no cookies, and no analytics on your input. The conversion logic runs entirely on your device, meaning your values never leave your browser. You can verify this by disconnecting from the internet and using the tool — it works fully offline once the page has loaded.
How many ounces are in a pound?
One pound contains exactly 16 avoirdupois ounces. This is an exact definition, not an approximation. Useful fractional references: 1/4 lb = 4 oz, 1/2 lb = 8 oz, 3/4 lb = 12 oz. Note that a troy pound (rarely used) contains only 12 troy ounces. When someone says 'pound' and 'ounce' without qualification, they mean the avoirdupois system used in everyday commerce.
How many milligrams are in a gram?
1 g = 1,000 mg exactly. This is a standard metric decimal relationship. Common references: one aspirin tablet = 325 mg, one vitamin C tablet = 500 mg, one caffeine capsule = 200 mg. The mg→g conversion is most frequently used in pharmaceutical dosages, nutrition labels, and laboratory measurements.
How many grams are in a pound?
1 lb = 453.59237 g (exact NIST definition). For quick estimates, use 454 g. Common references: 1/4 lb = 113.4 g (quarter-pounder burger patty), 1/2 lb = 226.8 g, 1 lb butter = 454 g (4 sticks). This conversion comes up frequently when adapting recipes between US and metric measurements. See also our volume converter for liquid ingredient conversions.
What is a grain and where is it used?
1 grain = 64.79891 mg = 0.0648 g. The grain is one of the oldest weight units still in active use, surviving in two specialized fields: pharmacy (aspirin was historically dosed in grains — 5 gr = 325 mg) and ballistics (bullet weights are measured in grains, e.g. a 9mm round = 115–147 gr). Try converting grains using the Specialty unit group above.
How do I convert between 斤 (jīn) and kilograms?
1 斤 (jīn, also called "catty") = 500 g = 0.5 kg. This is the most common everyday weight unit in mainland China, used for groceries, produce, and casual body weight references. 1 kg = 2 斤. Note: Southeast Asian catties differ (Malaysia: 1 catty = 604.79 g). This tool uses international standard units; for 斤 conversions, simply multiply the kg result by 2.
What do common everyday objects weigh?
Weight reference points for building intuition: a paper clip ≈ 1 g, a US quarter coin ≈ 5.67 g, a medium egg ≈ 50 g, a smartphone ≈ 172 g, a liter of water = 1,000 g (1 kg), a bowling ball ≈ 6 kg (13 lbs), an average adult ≈ 70 kg (154 lbs). These anchors help you estimate whether a conversion result is reasonable. For size comparisons, our length converter covers 16 units of distance.

Related Tools

View all tools →

Number Base Converter — Binary, Hex, Decimal & Octal

Conversion Tools

Convert numbers between binary, hexadecimal, decimal, octal, and any custom base (2-36) instantly. Free, private, no sign-up — all processing happens in your browser.

Image Compressor

Conversion Tools

Reduce image size up to 80% — compress JPEG, PNG & WebP in your browser, no upload needed. Batch 20 images, adjust quality, compare before & after. Free & private.

Length Unit Converter — Metric, Imperial & More

Conversion Tools

1 inch = 2.54 cm, 1 foot = 0.3048 m, 1 mile = 1.609 km. Convert between 16 length units instantly — metric, imperial, nautical & astronomical. Free, private, runs in your browser.

Temperature Converter — Celsius, Fahrenheit, Kelvin, Rankine

Conversion Tools

0 °C = 32 °F = 273.15 K = 491.67 °R. Convert Celsius, Fahrenheit, Kelvin & Rankine instantly — free, private, browser-based. Includes conversion formulas, step-by-step guides, and reference charts.

Volume & Liquid Measurement Converter — 15 Units

Conversion Tools

1 liter = 0.2642 US gallons, 1 cup = 236.6 mL. Convert volume & liquid capacity between 15 units — metric, US customary, imperial & cooking measurements. Free online converter, 100% private, runs in your browser.

Base64 Decoder & Encoder

Encoding & Formatting

Decode and encode Base64 online for free. Real-time conversion with full UTF-8 and emoji support. 100% private — runs in your browser. No signup needed.