When looking to purchase weights for exercise or other purposes, you may come across weights listed in pounds (lbs). However, the metric system is more commonly used worldwide, so you may need to convert the weight from pounds to kilograms (kg) to get a better sense of the actual weight.
Quick Answer
5 pounds is equal to 2.27 kg.
Detailed Answer
To convert pounds to kilograms, we need to use a conversion factor, as pounds and kilograms are different units of measurement.
The conversion rate between pounds and kilograms is:
1 lb = 0.453592 kg
So to convert 5 lbs to kg, we multiply the pounds by the conversion factor:
5 lbs x 0.453592 kg/lb = 2.26796 kg
Rounding to 2 decimal places, 5 lbs is equal to 2.27 kg.
Showing the Step-by-Step Work
Let’s break this conversion down step-by-step:
- Start with the amount in pounds: 5 lbs
- Multiply the pound amount by the conversion factor between lbs and kg:
5 lbs x 0.453592 kg/lb - The result is:
5 x 0.453592 = 2.26796 - Round to 2 decimal places:
2.26796 kg = 2.27 kg
Therefore, 5 pounds is equal to 2.27 kilograms when rounded to 2 decimal places.
Converting Other Pound Amounts to Kilograms
Using the same conversion factor, we can convert any pound amount to kilograms:
| Pounds | Conversion Calculation | Kilograms |
|---|---|---|
| 1 lb | 1 x 0.453592 kg/lb | 0.45 kg |
| 10 lbs | 10 x 0.453592 kg/lb | 4.54 kg |
| 25 lbs | 25 x 0.453592 kg/lb | 11.34 kg |
| 50 lbs | 50 x 0.453592 kg/lb | 22.68 kg |
This shows that the same process can be used to convert any pound amount to kilograms quickly and easily.
Typical Weights of Common Gym Items in Pounds vs Kilograms
Knowing typical weights of gym equipment in kilograms instead of pounds can be helpful for comparing items and making purchases if you are used to the metric system.
| Gym Item | Pounds | Kilograms |
|---|---|---|
| Barbell | 45 lbs | 20 kg |
| EZ Curl Bar | 20 lbs | 9 kg |
| Standard Plate | 2.5, 5, 10 lbs | 1.25, 2.5, 5 kg |
| Dumbbell | 5, 8, 10, 15 lbs | 2, 4, 5, 8 kg |
| Kettlebell | 5, 10, 15, 20 lbs | 2, 5, 8, 10 kg |
This table shows some of the most common weights of gym items in both pounds and the converted kilograms. Items like barbells, plates, and dumbbells can usually be found in both pound and kilogram increments.
When to Use Pounds vs Kilograms
In day to day life, pounds or kilograms may be more readily used depending on the country and context:
- Pounds are primarily used in the United States, Canada, and the United Kingdom.
- Kilograms are used throughout most of the rest of the world including all of Europe, Asia, Africa, Oceania, and South America.
- In science and for official records, kilograms are most often used worldwide.
- Recipes may use pounds, ounces, or grams depending on the origin.
- Weight limits on roads and at airports are listed in pounds in the US and kilograms internationally.
- Gym weights are often listed in pounds at American gyms and in kilograms elsewhere.
Knowing when each unit is more commonly used can help you convert between pounds and kilograms more easily.
Should I Buy Pound or Kilogram Weights?
If you are purchasing weights such as dumbbells or plates, you may be given the choice between pounds or kilograms. Here are some factors to help choose:
- If using the weights primarily in the US, pound increments may be easier
- If using weights internationally, kilogram increments are more universal
- Pound weights generally offer smaller increments such as 2.5 or 5 lbs vs kilogram plates in 1 or 2 kg increments
- Kilogram weights can have decimals such as 1.25 kg plates, allowing similar small increments
- Choose whatever weight increments make creating your desired total weights easiest – you can mix pound and kilogram plates on the same barbell
The most important factor is choosing weights that allow you to comfortably progress and create useful total amounts for your exercises and fitness level.
Quick Weight Conversions
Here are some quick pound to kilogram conversions for common weight amounts:
| Pounds | Kilograms |
|---|---|
| 5 lbs | 2.27 kg |
| 10 lbs | 4.54 kg |
| 25 lbs | 11.34 kg |
| 45 lbs (typical barbell) | 20.41 kg |
| 100 lbs | 45.36 kg |
Use this for quick reference when comparing gym weight amounts in pounds vs kilograms.
Why Metric Weights are Preferred Scientifically
When recording weights for official, scientific, or medical purposes, metric units like grams and kilograms are preferred over imperial units like pounds:
- The metric system is used universally in science for consistency
- Metric weights are more precise, using decimals rather than fractions
- Converting between units is easier in the metric system
- Metric avoids confusion between pounds for force and pounds for mass
- Metric scales offer smaller increments for better resolution and precision
While pounds may still be used informally or for athletes and gym weights, kilograms are the scientifically preferred unit for weight.
Weight Conversion Formula
The formula for converting pounds (lbs) to kilograms (kg) is:
kg = lbs x 0.453592
Where 0.453592 is the constant conversion factor between the units.
The conversion from kg to lbs uses the same formula rearranged:
lbs = kg / 0.453592
This simple formula allows easy conversion in both directions for any weight amounts.
Conclusion
In summary:
- 5 pounds is equal to 2.27 kilograms
- To convert, multiply pounds by the conversion factor 0.453592
- Kilograms are preferred scientifically and throughout most of the world
- Pounds are more commonly used for gym weights in the US
- Choose pound or kilogram plates based on your needs and location
- Use the conversion formula lbs = kg x 0.453592 to convert weights in either direction
Knowing how to convert between pounds and kilograms allows you to compare weight amounts easily and make informed purchasing decisions when buying weights.