Last updated: 2026-02-11
Quick Answer
Use this rebar weight calculator to convert bar size + length + quantity into total rebar weight (lb), with an optional waste percentage for laps/splices and an optional material cost estimate. It’s built for contractor takeoffs when you need fast, citable numbers for ordering and pricing.
Inputs you’ll need
- Rebar size (#3 to #11)
- Length per piece (ft)
- Quantity (pieces)
- Waste/overage % (optional)
- Price per pound (optional)
Related tools: Concrete Calculator and Concrete Cost Per Yard Calculator.
We use nominal bar weights (lb/ft) commonly used for takeoffs and ordering.
Common stock lengths: 20 ft, 40 ft
Typical: 3–10% depending on laps/splices/cuts
Assumptions
- Weight is calculated using nominal lb/ft for the selected bar size.
- Overage is applied to total length (common for laps, hooks, cuts, and waste).
- Does not include chairs/ties/couplers or fabrication/placing labor.
Rebar Weight Results
Weight per Piece
13.36 lb
Total Length (w/ waste)
210.0 ft
Total Weight
140.3 lb
Estimated Material Cost
—
Detailed Breakdown
Tip: If you buy by the ton, divide pounds by 2,000 to get short tons.
12,800+ estimates calculated this month
Common Rebar Sizes (Reference Table)
| Bar size | Diameter (in) | Weight (lb/ft) | 100 ft weighs |
|---|---|---|---|
| #3 | 0.375 | 0.376 | 37.6 lb |
| #4 | 0.500 | 0.668 | 66.8 lb |
| #5 | 0.625 | 1.043 | 104.3 lb |
| #6 | 0.750 | 1.502 | 150.2 lb |
| #7 | 0.875 | 2.044 | 204.4 lb |
| #8 | 1.000 | 2.67 | 267.0 lb |
| #9 | 1.128 | 3.4 | 340.0 lb |
| #10 | 1.270 | 4.303 | 430.3 lb |
| #11 | 1.410 | 5.313 | 531.3 lb |
Rebar Weight & Pricing Guide
Weight per foot by bar size, pricing data, and quantity calculation methods.
Rebar Weight Per Foot by Size
Rebar weight increases proportionally with diameter squared. Knowing weight per foot is essential for ordering, shipping, and structural calculations.
- #3 (3/8"): 0.376 lb/ft
- #4 (1/2"): 0.668 lb/ft
- #5 (5/8"): 1.043 lb/ft
- #6 (3/4"): 1.502 lb/ft
- #7 (7/8"): 2.044 lb/ft
- #8 (1"): 2.670 lb/ft
- #9 (1-1/8"): 3.400 lb/ft
- #10 (1-1/4"): 4.303 lb/ft
Standard rebar comes in 20-foot lengths. A bundle of #4 rebar (typically 50 pieces) weighs approximately 668 lbs.
Key Takeaways
- #4 (1/2"): 0.668 lb/ft — most common residential
- #5 (5/8"): 1.043 lb/ft
- Standard length: 20 feet per stick
Rebar Pricing in 2026
Rebar costs $0.50–$1.50 per linear foot depending on size, with #4 rebar averaging $0.65–$0.85/ft at retail.
- #3 rebar: $0.40–$0.65/ft ($8–$13 per 20-ft stick)
- #4 rebar: $0.65–$0.85/ft ($13–$17 per stick)
- #5 rebar: $0.80–$1.20/ft ($16–$24 per stick)
- #6 rebar: $1.00–$1.50/ft ($20–$30 per stick)
- Epoxy-coated (green): Add 30–50% premium for corrosion resistance
Buy from a steel supplier or rebar fabricator for bulk pricing 20–40% below big-box store retail.
Key Takeaways
- #4 rebar: $0.65–$0.85/ft retail
- Epoxy-coated adds 30–50% premium
- Steel suppliers: 20–40% cheaper than retail
How to Calculate Total Rebar Needed
Total rebar = (slab length ÷ spacing + 1) × slab width, for each direction, plus 30–40 times the bar diameter for each lap splice.
- Grid calculation: Count bars in each direction based on spacing
- Lap splice length: 30–40× bar diameter (24" for #4 rebar minimum)
- Waste factor: Add 5–10% for cutting waste and overlaps
- Example: 20×20 ft slab at 12" OC = 21 bars each way × 20 ft = 840 linear feet of rebar
Convert linear feet to weight for ordering: 840 ft of #4 = 561 lbs (840 × 0.668 lb/ft).
Key Takeaways
- Count bars: (dimension ÷ spacing + 1) each direction
- Lap splice: 24" minimum for #4 rebar
- Add 5–10% waste factor
Common rebar weight examples (5 examples)
These examples help you confirm the calculator output. (Total weight ignores waste unless noted.)
| Case | Inputs | Expected |
|---|---|---|
| 1 | #4, 20 ft, qty 10, 0% waste | Total length 200 ft; weight = 200 × 0.668 = 133.6 lb |
| 2 | #5, 20 ft, qty 10, 0% waste | Weight = 200 × 1.043 = 208.6 lb |
| 3 | #3, 10 ft, qty 50, 0% waste | Total length 500 ft; weight = 500 × 0.376 = 188.0 lb |
| 4 | #8, 40 ft, qty 25, 0% waste | Total length 1,000 ft; weight = 1,000 × 2.67 = 2,670 lb |
| 5 | #4, 20 ft, qty 10, 5% waste | Length w/ waste 210 ft; weight = 210 × 0.668 = 140.28 lb |
Common mistakes (avoid these)
- Forgetting waste for lap splices, hooks, and cutoffs.
- Mixing up feet vs inches on cut lengths.
- Pricing only the steel and forgetting chairs, ties, delivery, and placing labor.
If you’re assembling a full estimate, our Construction Bid Template can help keep your takeoff and pricing organized.
How to Use This Calculator
Pick the rebar size
Select a common bar size (#3 through #11). The calculator uses nominal weights in pounds per foot (lb/ft).
Enter length and quantity
Enter the length per piece (in feet) and number of pieces. Use stock lengths (20 ft / 40 ft) or your cut length.
Add waste/overage
Add a waste percentage to cover laps/splices, hooks, cuts, and field waste. 3–10% is typical depending on detailing.
Optional: price it
Enter your rebar price per pound to estimate material cost. (Fabrication, placing labor, chairs, and ties are not included.)
Rebar Weight Formulas
Total Length (ft) = Length per Piece (ft) × Quantity
Total Length w/ Waste = Total Length × (1 + Waste%/100)
Total Weight (lb) = Total Length w/ Waste × Weight per Foot (lb/ft)
Estimated Cost = Total Weight × Price per lbWhere:
- Weight per Foot
- = Nominal lb/ft based on bar size (#3–#11)
- Waste%
- = Overage to cover laps/splices, hooks, cuts, and jobsite waste
- Price per lb
- = Optional material price; enter 0 to skip cost estimate
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Frequently Asked Questions
How do you calculate rebar weight?
What is the weight per foot for #4 rebar?
How many pounds is a 20-foot stick of rebar?
How much waste should I add for rebar takeoffs?
How do I convert rebar pounds to tons?
Does this calculator include lap splices and hooks automatically?
Is rebar priced per pound or per stick?
What else should I include in a rebar estimate?
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