Table of Contents
| Steel Weight Calculator at First Glance
Commonly used formula on site: Weight of steel per meter= d²/162
For the Most Accurate Result: Weight of steel per meter= (π d² /4 ) * 7850 Where, Pie (π) = 22/7 & Density of steel= 7850kg/m³ |
Pro Steel Weight Calculator
Pro Steel Weight Calculator
Read Also: Length of steel bar in different countries
1. Steel Weight Formula
I have seen most supervisors or engineers using d²/162 on site to calculate the approximate weight of a steel bar. But for an accurate calculation, I suggest using the formula (π d² /4) * 7850.
Do they provide the same value??
| Weight of steel per meter= d²/162 | Weight of steel per meter= (π d² /4 ) * 7850 |
E.g., weight of a 12 mm dia bar with 1m length Weight of steel per meter= 12²/162 = 0.89 kg | E.g., weight of a 12 mm dia bar with 1m length Weight of steel per meter= (π x 0.012² / 4 ) * 7850 = 0.888kg |
Both formulas provide nearly the same value. For a 1 m bar, the difference is very small, but for large structures that require a large quantity of bars, this difference may create a problem.
How are they interconnected?
Weight of steel per meter in kg = Volume * Density = Area * L* Density = (π d² /4) * (1*1000) * [7850 / (1000*1000*1000)] (Note: Area of a circular base = (π d² /4) , Length = 1m = 1000 mm taken , d = diameter in mm Density of steel= 7850kg/m³ = [7850 / (1000*1000*1000)] kg /mm³ ) = 0.0061678571 d² = d² / 162.130 ≈ d² / 162 | Weight of steel per meter in kg = Volume * Density = Area * L* Density = (π d² /4) * 1 * 7850 ( All in SI unit ) = (π d² /4 ) * 7850 |
Both are derived in a similar way, but not considering the digits after the decimal point in the first formula is the reason behind the lower accuracy.
2. Unit Weight of Steel Bars per Meter
I have provided the table containing the unit weights of mostly used rebar diameters.
| Bar Diameter (mm) | Unit Weight (kg/m) |
| 6 | 0.222 |
| 8 | 0.395 |
| 10 | 0.617 |
| 12 | 0.888 |
| 16 | 1.579 |
| 20 | 2.466 |
| 25 | 3.853 |
| 28 | 4.835 |
| 32 | 6.313 |
| 36 | 7.994 |
| 40 | 9.864 |
| 45 | 12.487 |
| 50 | 15.413 |
3. Steel Bar Weight Chart (6mm to 50mm)
| Bar Diameter (mm) | Unit Weight (kg/m) | Weight for 10 m (kg) | Weight for 50 m (kg) |
| 6 | 0.222 | 2.220 | 11.101 |
| 8 | 0.395 | 3.948 | 19.738 |
| 10 | 0.617 | 6.166 | 30.828 |
| 12 | 0.888 | 8.882 | 44.412 |
| 16 | 1.579 | 15.791 | 78.957 |
| 20 | 2.466 | 24.662 | 123.312 |
| 25 | 3.853 | 38.543 | 192.713 |
| 28 | 4.835 | 48.347 | 241.735 |
| 32 | 6.313 | 63.134 | 315.670 |
| 36 | 7.994 | 79.938 | 399.688 |
| 40 | 9.864 | 98.436 | 492.180 |
| 45 | 12.487 | 124.869 | 624.346 |
| 50 | 15.413 | 154.134 | 770.671 |
a. 6mm Steel Bar Weight
Weight of steel per meter
= (π d² /4 ) * 7850 = (π 0.006² /4 ) * 7850
= 0.222 kg
b. 8mm Steel Bar Weight
Weight of steel per meter
= (π d² /4 ) * 7850
= (π 0.008² /4 ) * 7850
= 0.395 kg
c. 10mm Steel Bar Weight
Weight of steel per meter
= (π d² /4 ) * 7850
= (π 0.01² /4 ) * 7850
= 0.617 kg
d. 12mm Steel Bar Weight
Weight of steel per meter
= (π d² /4 ) * 7850
= (π 0.012² /4 ) * 7850
= 0.888 kg
e. 16mm Steel Bar Weight
Weight of steel per meter
= (π d² /4 ) * 7850
= (π 0.016² /4 ) * 7850
= 1.579 kg
f. 20mm Steel Bar Weight
Weight of steel per meter
= (π d² /4 ) * 7850
= (π 0.02² /4 ) * 7850
= 2.466 kg
g. 25mm Steel Bar Weight
Weight of steel per meter
= (π d² /4 ) * 7850
= (π 0.025² /4 ) * 7850
= 3.853 kg
h. 28mm Steel Bar Weight
Weight of steel per meter
= (π d² /4 ) * 7850
= (π 0.028² /4 ) * 7850
= 4.835 kg
i. 32mm Steel Bar Weight
Weight of steel per meter
= (π d² /4 ) * 7850
= (π 0.032² /4 ) * 7850
= 6.313 kg
4. Difference Between Theoretical and Actual Steel Weight
I am using ( Weight of steel per meter= (π d² /4 ) * 7850 ) this formula for 8 years. Actual steel weight may vary slightly from theoretical steel weight because of manufacturing tolerances and the specific steel grade.
Variation between theoretical and actual steel weight may vary by ±2 %.
5. FAQs
a. How to calculate the weight of steel?
Ans: We can calculate the weight of steel using the formula: Weight of steel per meter= (π d² /4 ) * 7850 * Length
b. How to calculate the weight of a sheet of steel?
Ans: We can calculate the weight of a sheet of steel using the formula:
Weight of a sheet of steel = Volume * Density of Steel
= (l*b*h) * 7850
c. What is the weight of a 20mm steel bar?
Ans: The weight of a 20mm steel bar with a 1 m length is 2.466 kg.
d. How many kg is 16 mm steel?
Ans: 16 mm steel of a 1 m length weighs 1.579 kg.
e. How much is a 12 mm steel bar weight?
Ans: 12 mm steel of a 1 m length weighs 0.888 kg.
f. What is the density of commonly used construction steel?
Ans: The density of commonly used construction steel is 7850kg/m³.
| Written By | Er. Aneel Kunwar |
| Role | Site Engineer at A n B Engineering Consultancy |
| Experience | 5 years+ of practical construction experience |
| Technically reviewed by | Er. Bikas Kafle |
