Grams to kg and kg to grams converter

Grams to kg means moving the decimal point three places to the left: 2,500 g = 2.5 kg. Type grams and the kilograms follow as you type, with the pound and ounce values below; kilograms to grams works in the same box.

Example: Weight 2,500 · Direction: Grams to kg (g → kg) → Answer: 2,500 g = 2.5 kg. Source: BIPM – The International System of Units (SI Brochure, 9th edition). Updated: 5 October 2026.

Weight

Direction

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Result

Answer: 2,500 g = 2.5 kg
In US units: In US units: 5.512 lb or 88.185 oz.
Working: 2,500 g ÷ 1000 = 2.5 kg
Conversion chart: g kg
1 0.001
5 0.005
10 0.01
25 0.025
50 0.05
100 0.1
125 0.125
200 0.2
250 0.25
350 0.35
454 0.454
500 0.5
750 0.75
1,000 1
1,500 1.5
2,000 2
5,000 5
10,000 10
Weights worth knowing: Weight g kg
A paper clip 1 0.001
US nickel (5.000 g) 5 0.005
A 1 euro coin (7.5 g) 7.5 0.0075
A 100 g chocolate bar 100 0.1
Half a kilo of flour 500 0.5
One liter of water (about) 1,000 1
Newborn, about 3.5 kg 3,500 3.5
Checked-bag limit (23 kg) 23,000 23; 1 kg = 1000 g exactly (SI prefix kilo = 10³). The kilogram has been defined by the Planck constant since 20 May 2019; the old platinum-iridium cylinder no longer sets the unit.

g	kg
1	0.001
5	0.005
10	0.01
25	0.025
50	0.05
100	0.1
125	0.125
200	0.2
250	0.25
350	0.35
454	0.454
500	0.5
750	0.75
1,000	1
1,500	1.5
2,000	2
5,000	5
10,000	10

Weight	g	kg
A paper clip	1	0.001
US nickel (5.000 g)	5	0.005
A 1 euro coin (7.5 g)	7.5	0.0075
A 100 g chocolate bar	100	0.1
Half a kilo of flour	500	0.5
One liter of water (about)	1,000	1
Newborn, about 3.5 kg	3,500	3.5
Checked-bag limit (23 kg)	23,000	23

How it is calculated

Moving the decimal point

kilograms = grams ÷ 1000 and grams = kilograms × 1000. Because “kilo” means a thousand, the conversion is exact and needs no calculator: 750 g = 0.75 kg, 12 g = 0.012 kg, 1.5 kg = 1,500 g. Three places left for grams to kg, three places right for kg to grams.

Small amounts

For tiny quantities the converter keeps enough digits instead of rounding to zero: 0.5 g = 0.0005 kg, and 5 mg is 0.005 g, so 0.005 g = 0.000005 kg. If you need milligrams, remember 1 g = 1000 mg, so the chain is mg ÷ 1000 = g, g ÷ 1000 = kg, or mg ÷ 1,000,000 = kg.

Where it shows up

Baking: recipes in grams scale to kilograms when you buy: 1,500 g of flour is 1.5 kg.
Travel: airlines give the checked-bag limit in kilograms (often 23 kg, which is 23,000 g); a kitchen scale in grams helps you pack.
Babies: birth weights are recorded in grams and growth charts in kilograms: 3,500 g is 3.5 kg.
Pricing: shop labels show price per kg; a 250 g pack at 2.40 is 9.60 per kg.

A note on the kilogram

The kilogram is the only SI base unit with a prefix in its name, which is why the base unit is the kilogram and not the gram. Since 20 May 2019 it is fixed by the Planck constant (6.62607015 × 10⁻³⁴ J·s) rather than by the metal cylinder kept near Paris, so the factor of exactly 1000 to the gram never changes.

For the pound and ounce equivalents see the kg to lbs converter and grams to oz.

Frequently asked questions

How many kg is 1000 grams?

1,000 g = 1 kg. One thousand grams is exactly one kilogram.

How do I convert grams to kg?

Divide by 1000, or move the decimal point three places left: 750 g = 0.75 kg.

How many grams are in 2.5 kg?

2.5 kg = 2,500 g. Multiply kilograms by 1000.

What is 500 grams in kg?

500 g = 0.5 kg, half a kilogram, which is about 1.102 lb.

Is a gram the SI base unit?

No. The kilogram is the SI base unit. The gram is one thousandth of it and is used as the everyday unit for small amounts.

Sources and legal basis

As of: 5 October 2026 · Editorial policy