Rebar Weight Calculator
A rebar weight calculator multiplies bar count by length and the nominal weight per foot for the selected size. Enter equal-length bars of one size to get pounds and US short tons. Calculate different sizes or lengths separately, and check whether your bar lengths already include laps and bends.
Weight including allowance
2,190lb
- Total length
- 2,000 LF
- Weight per bar
- 20.86 lb
- In tons
- 1.10 tons
Formula: lb = bars × length ft × 1.043 lb/ft (#5), then + lap/waste %
Uses the listed nominal weight per foot for the selected bar size.
How the calculation works
Total length is bar count × length per bar. Multiply by the selected nominal pounds per foot for the unadjusted weight. The entered allowance increases total weight, while displayed total length and weight per bar remain before allowance.
For example, 100 bars at 20 feet each give 2,000 linear feet. A #5 bar uses 1.043 lb/ft, so the total is 2,086 pounds before allowance, or 2,190.3 pounds with an example 5% allowance. Divide pounds by 2,000 for short tons.
Use scheduled cut lengths where available. A single percentage is not a splice-design calculation. If laps, hooks, and bends are already included in the lengths, do not add them again through an allowance. Count separate dowels or additional bars as their own entries.
The table covers nominal bar sizes #3 through #11. It estimates steel weight, not required reinforcement or installed bar count. Use the reinforcement drawings and bar schedule to determine sizes, spacing, development, and splice requirements.
Reference values
| Bar size | Nominal weight |
|---|---|
| #3 | 0.376 lb/ft |
| #4 | 0.668 lb/ft |
| #5 | 1.043 lb/ft |
| #6 | 1.502 lb/ft |
| #7 | 2.044 lb/ft |
| #8 | 2.670 lb/ft |
| #9 | 3.400 lb/ft |
| #10 | 4.303 lb/ft |
| #11 | 5.313 lb/ft |
Frequently asked questions
How much does a 20-foot #5 bar weigh?
Using 1.043 lb/ft, it weighs 20.86 pounds before allowance.
Can I calculate mixed bar sizes?
Run each size and length group separately, then add the weights. The widget uses one size and one bar length at a time.
Does the allowance calculate lap length?
No. It adds a percentage to weight. Required lap lengths must come from the design; do not add a lap allowance if those lengths are already counted.
Does total length include the allowance?
No. Total length and weight per bar are unadjusted. Total pounds and tons include the entered percentage.