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Rebar Weight Calculator

Free rebar weight calculator for contractors. Calculate rebar weight (lb) from bar size, length, and quantity with optional waste and cost per pound.

1,000+ Contractors Reviewed by Pros By EstimationPro Team

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.

ft

Common stock lengths: 20 ft, 40 ft

pieces
%

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

Bar size#4
Nominal weight0.668 lb/ft
Diameter0.500 in
Base total length200.0 ft
Waste factor5%
Total length (with waste)210.0 ft
Total weight140.3 lb

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 sizeDiameter (in)Weight (lb/ft)100 ft weighs
#30.3750.37637.6 lb
#40.5000.66866.8 lb
#50.6251.043104.3 lb
#60.7501.502150.2 lb
#70.8752.044204.4 lb
#81.0002.67267.0 lb
#91.1283.4340.0 lb
#101.2704.303430.3 lb
#111.4105.313531.3 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 lb

Where:

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?
Rebar weight is calculated from total length and the bar's nominal weight per foot: Total weight (lb) = Total length (ft) × Weight (lb/ft). If you add waste, multiply total length by (1 + waste%).
What is the weight per foot for #4 rebar?
Nominal weight for #4 rebar is 0.668 lb/ft. A 20 ft stick of #4 weighs about 13.36 lb (before waste).
How many pounds is a 20-foot stick of rebar?
Multiply 20 ft by the bar's lb/ft. Example: #5 is 1.043 lb/ft, so a 20 ft stick weighs 20 × 1.043 = 20.86 lb.
How much waste should I add for rebar takeoffs?
For simple mats with long runs, 3–5% is common. For heavy splicing, hooks, congestion, and lots of cut pieces, plan 7–10%. Always follow the engineer's detailing for lap lengths and hooks.
How do I convert rebar pounds to tons?
Divide pounds by 2,000 to get short tons. Example: 4,000 lb = 2.0 tons.
Does this calculator include lap splices and hooks automatically?
No. This tool applies waste/overage as a simple percentage. If your plans specify lap splice lengths and hook details, include them by increasing waste or using cut lengths that already include required laps/hooks.
Is rebar priced per pound or per stick?
Both are used. Fabricators often price by ton (or by pound) for supply/fabrication, while yards may quote per stick for stock lengths. This calculator supports price per pound so it works for both styles.
What else should I include in a rebar estimate?
Besides steel weight, include chairs/spacers, ties, couplers, delivery, and placing labor. For larger pours, also consider pumping and finishing (see our concrete tools).

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