How do I calculate bar weight?

Bar weight = cross-section area × length × steel density (490 lb/ft³ for carbon steel). For round bar / rebar, area = π/4 × diameter². For square bar, area = side². For flat bar, area = width × thickness. The calculator handles round bar, rebar, plate, pipe, angle, and square tube shapes — pick the shape and enter dimensions, and it returns weight per foot, weight per piece, and total weight.

How does the calculator compute steel weight?

It calculates the cross-section area for your chosen shape (round bar, plate, pipe, angle, square tube), then multiplies by length and steel density of 490 lb/ft³ (7,850 kg/m³).

What's the density of steel used in the calculation?

490 lb per cubic foot, equivalent to 7,850 kg per cubic meter. This is standard for carbon steel and most structural steel grades.

How do I identify rebar size?

Rebar sizes are counted in eighths of an inch. #3 = 3/8", #4 = 4/8" = 1/2", #5 = 5/8", #6 = 3/4", and so on. The calculator covers these sizes.

What does #4 rebar weigh per foot?

#4 rebar (1/2" diameter) weighs 0.668 lb per linear foot. A standard 20 ft length weighs 13.36 lb. The calculator handles all standard rebar sizes (#3 through #11) automatically.

How many feet of #5 rebar weighs 100 pounds?

About 96 ft. #5 rebar weighs 1.043 lb/ft, so 100 ÷ 1.043 ≈ 95.9 ft. For ordering, round up — typical 20 ft sticks means 5 bars (100 ft total).

How much does a 4×8 sheet of 1/2 inch steel plate weigh?

A 4 ft × 8 ft × 1/2 in carbon steel plate weighs about 653 lb. The calculation: 48 × 96 × 0.5 in³ = 2,304 in³ = 1.333 ft³ × 490 lb/ft³ = 653 lb.

What's the weight difference between Schedule 40 and Schedule 80 pipe?

Schedule 80 has thicker walls. For 2" steel pipe: Sch 40 (0.154" wall) ≈ 3.66 lb/ft, Sch 80 (0.218" wall) ≈ 5.02 lb/ft — about 37% heavier. Use the actual wall thickness in the calculator for accurate results.

Does the calculator work for stainless steel or aluminum?

It uses carbon-steel density (490 lb/ft³). Stainless is ~2% heavier (~500 lb/ft³). For aluminum (~169 lb/ft³) or other alloys, multiply the result by the ratio of densities: (your density ÷ 490).

Does the calculator handle angle iron?

It approximates angle shapes as a solid round profile. The note flags this — use it for estimates, not for precise structural calculations. For exact angle weights, reference AISC steel tables.

What is the weight of steel?

Carbon steel weighs 490 lb per cubic foot (7,850 kg/m³). Per linear foot, common shapes weigh: #4 rebar (1/2") ≈ 0.668 lb/ft, #5 rebar (5/8") ≈ 1.043 lb/ft, 1" round bar ≈ 2.67 lb/ft, 1/2" steel plate ≈ 20.4 lb/ft², 2" Schedule 40 pipe ≈ 3.66 lb/ft. Use the calculator above for any shape and size.

How do I compute the weight of steel?

Weight = cross-section area × length × density. For carbon steel, density is 490 lb/ft³ (7,850 kg/m³). Convert your cross-section to square feet, multiply by length in feet, then multiply by density to get pounds. The calculator does this automatically for round bar, plate, pipe, angle, and square tube — just pick the shape and enter dimensions.

Steel Weight Calculator

Free online steel weight and bar weight calculator — round bar, rebar, plate, pipe, angle, and square tube. Get weight per foot and total weight by shape and length.

Steel Weight Calculator

Distance (ft)

Steel shape

Diameter / width

Wall thickness

Quantity

Results

Weight per foot

Weight per piece

Total weight

Need Construction Business Software?

These calculators are even more powerful inside The Blocks. During takeoffs, material quantities are calculated automatically from your measurements — no manual entry needed.

Learn more about Digital Takeoffs, AI Estimates, and Cost Catalog.

Web access — desktop, tablet & mobile
AI-powered plan takeoffs
Manual markup tools
Cost estimating & budgets
Bid management & proposals
CRM & contact management

MonthlyAnnualSave 20%

Seats:

$119 per seat × 1$119/mo

Total

$119/mo

$1,428/yr

How to Use This Calculator

Formula

Round bar: area = π/4 × d²Pipe: area = π/4 × (OD² − ID²)Plate: area = width × thicknessSquare tube: area = outer² − inner²weightPerFt = area(in²) × 490 lb/ft³ / 144

Parameters

Shape: Round bar, plate, pipe, angle, or square tube.
Diameter / Width: Outer dimension in inches or mm.
Wall Thickness: For hollow shapes or plate thickness.
Quantity: Number of identical pieces.

Results

Weight per Foot: Unit weight in lb per linear foot.
Weight per Piece: Weight of one piece at given length.
Total Weight: All pieces combined in lb.

Example

#4 Rebar (50 bars × 20 ft)

0.5" diameter round bar, 20 ft length, 50 pieces

area = π/4 × 0.25 = 0.196 in²weightPerFt = 0.196 × 490 / 144 = 0.668 lb/ftperPiece = 0.668 × 20 = 13.4 lbtotal = 13.4 × 50 = 668 lb

1/2" Steel Plate (4 ft × 8 ft sheet)

48" × 96" plate, 0.5" thickness, 1 sheet

area = 48 × 96 = 4,608 in²volume = 4,608 × 0.5 = 2,304 in³volumeFt³ = 2,304 / 1,728 = 1.333 ft³weight = 1.333 × 490 = 653 lb

2" Schedule 40 Pipe (100 ft run)

2.375" OD × 0.154" wall, 100 ft length, 1 run

outerArea = π/4 × 2.375² = 4.430 in²innerArea = π/4 × (2.375 − 2×0.154)² = 3.355 in²wallArea = 4.430 − 3.355 = 1.075 in²weightPerFt = 1.075 × 490 / 144 = 3.66 lb/fttotal = 3.66 × 100 = 366 lb

Common Use Cases

Rebar ordering and transport planning
Steel fabrication cost estimation
Structural steel weight checks
Pipe and tube material purchasing
Shipping freight class calculations
Crane and lift capacity verification

Notes

Steel density: 490 lb/ft³ (7,850 kg/m³) — standard for carbon and most structural steel grades.
Stainless steel is ~2% heavier (~500 lb/ft³ / 8,000 kg/m³).
Standard rebar weights per foot: #3 = 0.376 lb, #4 = 0.668 lb, #5 = 1.043 lb, #6 = 1.502 lb, #7 = 2.044 lb, #8 = 2.670 lb, #9 = 3.400 lb, #10 = 4.303 lb.
Angle shapes are approximated as a solid round profile — use for estimates only; reference AISC steel tables for structural design.
Schedule 40 vs Schedule 80: a 2" Sch 80 pipe (0.218" wall) weighs ~5.02 lb/ft vs Sch 40 at ~3.66 lb/ft — about 37% heavier.

Frequently Asked Questions

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Get in Touch

Zaur Zhanabekov

Sales

+1 347-962-1064 zaur@theblocks.app

Steel Weight Calculator

Free online steel weight and bar weight calculator — round bar, rebar, plate, pipe, angle, and square tube. Get weight per foot and total weight by shape and length.

Steel Weight Calculator

Distance (ft)

Steel shape

Diameter / width

Wall thickness

Quantity

Results

Weight per foot

Weight per piece

Total weight

Need Construction Business Software?

These calculators are even more powerful inside The Blocks. During takeoffs, material quantities are calculated automatically from your measurements — no manual entry needed.

Web access — desktop, tablet & mobile

AI-powered plan takeoffs

Manual markup tools

Cost estimating & budgets

Bid management & proposals

CRM & contact management

MonthlyAnnualSave 20%

Seats:

$119 per seat × 1$119/mo

Total

$119/mo

$1,428/yr

How to Use This Calculator

Formula

Round bar: area = π/4 × d²Pipe: area = π/4 × (OD² − ID²)Plate: area = width × thicknessSquare tube: area = outer² − inner²weightPerFt = area(in²) × 490 lb/ft³ / 144

Parameters

Shape: Round bar, plate, pipe, angle, or square tube.
Diameter / Width: Outer dimension in inches or mm.
Wall Thickness: For hollow shapes or plate thickness.
Quantity: Number of identical pieces.

Results

Weight per Foot: Unit weight in lb per linear foot.
Weight per Piece: Weight of one piece at given length.
Total Weight: All pieces combined in lb.

Example

#4 Rebar (50 bars × 20 ft)

0.5" diameter round bar, 20 ft length, 50 pieces

area = π/4 × 0.25 = 0.196 in²weightPerFt = 0.196 × 490 / 144 = 0.668 lb/ftperPiece = 0.668 × 20 = 13.4 lbtotal = 13.4 × 50 = 668 lb

1/2" Steel Plate (4 ft × 8 ft sheet)

48" × 96" plate, 0.5" thickness, 1 sheet

area = 48 × 96 = 4,608 in²volume = 4,608 × 0.5 = 2,304 in³volumeFt³ = 2,304 / 1,728 = 1.333 ft³weight = 1.333 × 490 = 653 lb

2" Schedule 40 Pipe (100 ft run)

2.375" OD × 0.154" wall, 100 ft length, 1 run

outerArea = π/4 × 2.375² = 4.430 in²innerArea = π/4 × (2.375 − 2×0.154)² = 3.355 in²wallArea = 4.430 − 3.355 = 1.075 in²weightPerFt = 1.075 × 490 / 144 = 3.66 lb/fttotal = 3.66 × 100 = 366 lb

Common Use Cases

Rebar ordering and transport planning
Steel fabrication cost estimation
Structural steel weight checks
Pipe and tube material purchasing
Shipping freight class calculations
Crane and lift capacity verification

Notes

Steel density: 490 lb/ft³ (7,850 kg/m³) — standard for carbon and most structural steel grades.
Stainless steel is ~2% heavier (~500 lb/ft³ / 8,000 kg/m³).
Standard rebar weights per foot: #3 = 0.376 lb, #4 = 0.668 lb, #5 = 1.043 lb, #6 = 1.502 lb, #7 = 2.044 lb, #8 = 2.670 lb, #9 = 3.400 lb, #10 = 4.303 lb.
Angle shapes are approximated as a solid round profile — use for estimates only; reference AISC steel tables for structural design.
Schedule 40 vs Schedule 80: a 2" Sch 80 pipe (0.218" wall) weighs ~5.02 lb/ft vs Sch 40 at ~3.66 lb/ft — about 37% heavier.