0.001 kg, because a thousand grams make one kilogram. The pattern holds at every size: 10 g is 0.01 kg, 100 g is 0.1 kg, 250 g is 0.25 kg, 500 g is 0.5 kg, 750 g is 0.75 kg and 1,000 g is exactly 1 kg. Dividing by a thousand moves the decimal point three places to the left, so 12,345 g reads 12.345 kg.

What is the formula for grams to kilograms?

Kilograms = grams / 1,000, and grams = kilograms × 1,000 in the other direction. Kilo is the SI prefix for a thousand, which is why this is a single division and never a lookup: 1,500 / 1,000 = 1.5 kg, 2,500 / 1,000 = 2.5 kg, and 80 / 1,000 = 0.08 kg. The swap button between the two boxes reverses the pair, so this page turns into a kilograms to grams converter without a reload.

Is 1,000 g exactly 1 kg, or is it rounded?

Exactly: the kilogram is the SI base unit of mass and a gram is one thousandth of it, so 1,000 g = 1 kg and 2,000 g = 2 kg by definition. Decimal-rational arithmetic preserves the written input. Dividing a finite decimal by 1,000 terminates, but the displayed and copied result still rounds when it exceeds twelve significant digits. Other rows, such as pounds or stone, can have nonterminating decimals under their exact definitions.

0.5 kg, half a kilo. The pack sizes people usually arrive with work the same way: 125 g is 0.125 kg, 200 g is 0.2 kg, 400 g is 0.4 kg, 750 g is 0.75 kg, 1,500 g is 1.5 kg and 2,500 g is 2.5 kg. The result appears as you type, with no button to press, and Copy result copies it exactly as printed, without the thousands separators, so it pastes straight into a spreadsheet.

What is 500 g in pounds and ounces?

1.10231131092 lb, or 17.6369809748 oz, and both are already on screen: the list under the answer converts into every common mass unit at once instead of making you pick one target. For 1,000 g that list reads 1 kg, 2.20462262185 lb, 35.2739619496 oz, 0.157473044418 st, 1,000,000 mg and 0.001 t. The figures come from the exact definitions, since the international pound is 0.45359237 kg and the ounce is a sixteenth of that pound.

Why does a very small amount show as 1e-7?

Because the display switches to exponential notation below 0.000001, where a decimal answer becomes a row of zeros to count. So 0.001 g still prints in full as 0.000001 kg, while 0.0001 g prints as 1e-7 kg, which is 0.0000001. Nothing has gone wrong; for masses that small the milligram row under the answer is the easier one to read, since 0.0001 g is 0.1 mg.

Can I see milligrams, tonnes or stone as well?

They are already there. Under the answer the same mass is listed in milligrams, kilograms, tonnes, ounces, pounds, stone and US short tons, so 2,500 g reads 2.5 kg, 0.0025 t and 5.51155655462 lb at once. One switch in the readout adds the three uncommon mass units, long tons, carats and grains, and the readout also names the category, Mass, and its base unit, the kilogram. Typing something that is not a number shows a message saying so rather than a wrong answer.

Why does this page open on grams and kilograms when I last converted something else?

This focused page opens on Gram and Kilogram, while preserving the main converter’s saved unit pair. When storage is usable, a saved value and uncommon-unit preference can travel between pages. Its suffix must still match From. Valid deliberate scalar edits can save those fields after a short delay; invalid or incomplete drafts preserve the saved record. Unusable or conflicting records remain until you use Forget saved settings, which keeps the current conversion on screen. Your input and converted values are calculated in the browser and are not uploaded by the converter. The definitions arrive with the page, so conversion needs no external data lookup and keeps working offline after the page has loaded. The core conversion needs no account.

G to Kg Converter

A kilogram is exactly 1,000 grams, so grams to kilograms is one division: kg = g / 1,000, which is the decimal point moving three places to the left. That turns 1 g into 0.001 kg, 250 g into 0.25 kg, 500 g into 0.5 kg and 1,000 g into exactly 1 kg. The relation is a definition rather than a measurement, since the kilogram is the SI base unit of mass and the gram is defined as one thousandth of it, so nothing is rounded to make it come out even. This page opens the converter with grams in the From box and kilograms in the To box whatever pair you converted last, answers as you type, and prints the same mass in milligrams, tonnes, ounces, pounds, stone and US short tons under the answer, each to twelve significant digits and each with its own Copy button.

From

To0.001

Category: Mass

Base unit: kilogram

Uncommon units: Show 3 more

Ounces and pounds are avoirdupois mass. Tonne is metric, short ton is US and long ton is UK; fluid ounces belong to Volume.

Results round to 12 significant digits using the listed unit definitions. Input must have a finite numeric magnitude and at most 512 significant digits. Type a single decimal or scientific number; a matching From unit suffix is accepted. Commas and grouped spaces separate thousands; decimal commas, fractions and compound measurements are refused.

1 g in every mass unit

Milligrammg
1,000
Kilogramkg
0.001
Tonnet
0.000001
Ounceoz
0.0352739619496
Poundlb
0.00220462262185
Stonest
0.000157473044418
Short ton (US)ton
0.00000110231131092

Selectable complete conversion

Unit Converter — Mass
Input: 1 (Gram, g)
Result: 0.001 kg (Kilogram)
Displayed values round to 12 significant digits.
Ounces and pounds are avoirdupois mass. Tonne is metric, short ton is US and long ton is UK; fluid ounces belong to Volume.
All other units:
Milligram (mg): 1000
Kilogram (kg): 0.001
Tonne (t): 0.000001
Ounce (oz): 0.0352739619496
Pound (lb): 0.00220462262185
Stone (st): 0.000157473044418
Short ton (US) (ton): 0.00000110231131092
Long ton (UK) (long ton): 9.84206527611e-7
Carat (ct): 5
Grain (gr): 15.4323583529

Common questions

How many kg is 1 g?: 0.001 kg, because a thousand grams make one kilogram. The pattern holds at every size: 10 g is 0.01 kg, 100 g is 0.1 kg, 250 g is 0.25 kg, 500 g is 0.5 kg, 750 g is 0.75 kg and 1,000 g is exactly 1 kg. Dividing by a thousand moves the decimal point three places to the left, so 12,345 g reads 12.345 kg.
What is the formula for grams to kilograms?: Kilograms = grams / 1,000, and grams = kilograms × 1,000 in the other direction. Kilo is the SI prefix for a thousand, which is why this is a single division and never a lookup: 1,500 / 1,000 = 1.5 kg, 2,500 / 1,000 = 2.5 kg, and 80 / 1,000 = 0.08 kg. The swap button between the two boxes reverses the pair, so this page turns into a kilograms to grams converter without a reload.
Is 1,000 g exactly 1 kg, or is it rounded?: Exactly: the kilogram is the SI base unit of mass and a gram is one thousandth of it, so 1,000 g = 1 kg and 2,000 g = 2 kg by definition. Decimal-rational arithmetic preserves the written input. Dividing a finite decimal by 1,000 terminates, but the displayed and copied result still rounds when it exceeds twelve significant digits. Other rows, such as pounds or stone, can have nonterminating decimals under their exact definitions.
What is 500 g in kg?: 0.5 kg, half a kilo. The pack sizes people usually arrive with work the same way: 125 g is 0.125 kg, 200 g is 0.2 kg, 400 g is 0.4 kg, 750 g is 0.75 kg, 1,500 g is 1.5 kg and 2,500 g is 2.5 kg. The result appears as you type, with no button to press, and Copy result copies it exactly as printed, without the thousands separators, so it pastes straight into a spreadsheet.
What is 500 g in pounds and ounces?: 1.10231131092 lb, or 17.6369809748 oz, and both are already on screen: the list under the answer converts into every common mass unit at once instead of making you pick one target. For 1,000 g that list reads 1 kg, 2.20462262185 lb, 35.2739619496 oz, 0.157473044418 st, 1,000,000 mg and 0.001 t. The figures come from the exact definitions, since the international pound is 0.45359237 kg and the ounce is a sixteenth of that pound.
Why does a very small amount show as 1e-7?: Because the display switches to exponential notation below 0.000001, where a decimal answer becomes a row of zeros to count. So 0.001 g still prints in full as 0.000001 kg, while 0.0001 g prints as 1e-7 kg, which is 0.0000001. Nothing has gone wrong; for masses that small the milligram row under the answer is the easier one to read, since 0.0001 g is 0.1 mg.
Can I see milligrams, tonnes or stone as well?: They are already there. Under the answer the same mass is listed in milligrams, kilograms, tonnes, ounces, pounds, stone and US short tons, so 2,500 g reads 2.5 kg, 0.0025 t and 5.51155655462 lb at once. One switch in the readout adds the three uncommon mass units, long tons, carats and grains, and the readout also names the category, Mass, and its base unit, the kilogram. Typing something that is not a number shows a message saying so rather than a wrong answer.
Why does this page open on grams and kilograms when I last converted something else?: This focused page opens on Gram and Kilogram, while preserving the main converter’s saved unit pair. When storage is usable, a saved value and uncommon-unit preference can travel between pages. Its suffix must still match From. Valid deliberate scalar edits can save those fields after a short delay; invalid or incomplete drafts preserve the saved record. Unusable or conflicting records remain until you use Forget saved settings, which keeps the current conversion on screen. Your input and converted values are calculated in the browser and are not uploaded by the converter. The definitions arrive with the page, so conversion needs no external data lookup and keeps working offline after the page has loaded. The core conversion needs no account.

Results round to 12 significant digits using the listed unit conventions. Many factors are exact definitions; psi and parsec use rounded coefficients. Temperature includes scale offsets. Days and weeks are fixed-duration units, and unit conversion does not determine calendar dates, ambient pressure or a software label’s convention.