Why is rebar sold by the ton?

Steel commodities are traded by weight globally because weight reflects material content and production cost. Pricing per ton is consistent across bar sizes — a ton of #4 and a ton of #8 contain the same mass of steel.

Can I calculate the combined weight of multiple bar sizes?

Yes. Use Multi-bar mix mode and add a row for each bar size. Enter footage, stock length, and waste per size. The calculator shows individual weights as a percentage of total steel plus a combined tonnage.

What is the weight of a 20-foot rebar bar?

Weight of a single 20-foot stock bar per ASTM: #3 = 7.5 lbs, #4 = 13.4 lbs, #5 = 20.9 lbs, #6 = 30.0 lbs, #7 = 40.9 lbs, #8 = 53.4 lbs, #9 = 68.0 lbs, #10 = 86.1 lbs.

Can I calculate rebar weight in kilograms?

Yes. All results include weight in kg alongside lbs and US tons. The Target Weight mode also accepts input in kg. The calculator uses 1 lb = 0.453592 kg for all conversions.

What is a standard rebar stock bar length?

20-foot bars are the most common standard stock length in North America for #3–#8 bars. Some suppliers also offer 30-foot and 40-foot lengths. Enter any stock length in the calculator to get the exact bar count to order.

How accurate are ASTM rebar unit weights?

ASTM A615/A706 theoretical unit weights are highly accurate for estimation. ASTM allows ±3.5% weight tolerance per bar and per lot. For structural or certified-weight applications, verify with mill test reports from your supplier.

What bars does the rebar weight calculator cover?

The calculator covers #3 through #10 deformed bars per ASTM A615/A706, which accounts for the vast majority of concrete reinforcement applications from residential slabs to bridge decks.

Can I estimate the cost of a rebar order?

Yes. Enter a price per US ton to generate a material cost estimate. The calculator multiplies your total tonnage by the per-ton price, matching standard steel supplier invoicing. Add a delivery cost for a complete project total.

What is the difference between rebar weight and rebar quantity calculators?

A rebar quantity calculator starts from a slab area and spacing to produce footage and weight — it is a design tool. A rebar weight calculator starts from a known footage or tonnage and converts between units — it is a procurement and logistics tool. Both serve different stages of a concrete project.

Rebar Weight Calculator

Q: How much does rebar weigh per foot?

Rebar weight per foot per ASTM A615/A706: #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. Actual mill weights may vary ±3.5%.

Q: How do I convert rebar linear footage to tons?

Multiply total linear footage by the unit weight (lb/ft) for your bar size, then divide by 2,000. Example: 1,000 ft of #5 × 1.043 lb/ft = 1,043 lbs ÷ 2,000 = 0.522 US tons.

Q: How do I convert rebar weight to linear footage?

Divide the weight in lbs by the unit weight (lb/ft) for your bar size. Example: 2,000 lbs ÷ 1.043 lb/ft = 1,918 ft of #5 bar. Use the Target Weight mode in our calculator to do this automatically.

Q: What is the difference between ASTM A615 and ASTM A706 rebar weight?

ASTM A615 and A706 specify identical theoretical unit weights for each bar size — the standards differ in chemistry and mechanical properties, not weight. Weight calculations apply equally to both grades.

Q: How many linear feet are in a ton of rebar?

Linear feet per US ton by bar size: #3 = 5,319 ft, #4 = 2,994 ft, #5 = 1,918 ft, #6 = 1,331 ft, #7 = 979 ft, #8 = 749 ft, #9 = 588 ft, #10 = 465 ft.

Q: What waste percentage should I use for rebar weight?

Use 10% for standard rectangular layouts with normal laps. Use 15% for complex layouts with many bends, hooks, or irregular shapes. Waste covers lap splice lengths, hooks, and off-cut trim.

Reviewed by Engr. Talha Tariq | PEC License #: PEC-CIVIL-37815 | Last updated: 2026-03-27

Convert rebar linear footage to weight in lbs, US tons, and kg using ASTM A615 and A706 published unit weights. Supports single bar size, multi-bar mix for up to six bar types with individual waste factors, and reverse lookup from a target weight to equivalent footage and bars to order. Includes per-ton steel pricing for full procurement cost estimation.

Rebar Weight Calculator

Convert rebar linear footage to weight, mix multiple bar sizes for combined tonnage, or reverse-calculate footage from a target weight. Results appear after you press Calculate.

Estimate Mode

Project Type

Presets load sensible defaults. Override any value below.

Step 1 — Calculation Mode

Step 2 — Bar & Footage

Bar Size

ASTM A615 / A706 deformed bar.

Total linear footage

Net footage from your material takeoff.

Waste factor

Lap splices, off-cuts, hooks.

10% typical; 15% for complex layouts

Selected — #4 bar properties

Diameter: 0.5" · Area: 0.2 in² · Weight: 0.668 lb/ft · 0.994 kg/m

Driveways, patios, residential footings

Step 3 — Procurement & Cost

Stock bar length

Standard purchased bar length.

Used to calculate bars to order

Price per ton (optional)

$/ton

Commercial steel is priced per US ton.

Actions

Enter values above and press Calculate to reveal results.

How to Calculate Rebar Weight for Concrete Projects

The Rebar Weight Calculator is a procurement and logistics tool that converts rebar linear footage to weight in pounds, US tons, and kilograms — and can also work in reverse, converting a known steel tonnage specification back to the equivalent linear footage and bar count. It uses ASTM A615 and A706 published unit weights for deformed bars #3 through #10, giving accurate results that match supplier invoices and structural engineer specifications.

This calculator solves three distinct problems that contractors, estimators, and engineers encounter on every reinforced concrete project: converting a takeoff footage list to a delivery weight for freight planning, combining multiple bar sizes into a single total tonnage for commercial procurement, and reverse-calculating footage from a weight-based specification on structural drawings. All three modes are available in one tool, with optional per-ton steel pricing for full cost estimation.

Key Features of the Rebar Weight Calculator

Three calculation modes

Single bar size (footage → weight), Multi-bar mix (up to 6 sizes → combined tonnage), and Target weight (weight → footage reverse lookup) — all in one calculator.

ASTM A615 / A706 weight table

Built-in unit weights for #3 through #10 deformed bars per ASTM A615/A706, showing diameter, cross-sectional area, lb/ft, and kg/m. Active bars are highlighted.

Multi-bar mix with percentage breakdown

Enter up to 6 different bar sizes with individual footage, stock length, and waste. See each bar's weight as a percentage of total steel — useful for procurement and logistics.

Reverse weight-to-footage calculator

Enter a target weight from a structural spec, delivery manifest, or budget, and the calculator tells you the equivalent footage and bars to order.

Commercial per-ton pricing

Steel is quoted per US ton on commercial projects. Enter a price per ton and the calculator produces material cost and grand total — matching how steel suppliers invoice.

Bars to order output

Enter your stock bar length (typically 20 ft) and the calculator rounds up to the nearest whole bar, giving you the exact purchase quantity for your order.

Dual unit support — imperial and metric

Enter footage in feet or metres; enter weight targets in lbs, US tons, or kg. All conversions are handled internally using ASTM standard values.

Waste factor per bar type

Apply a different waste percentage to each bar size in multi-bar mode — useful when some sizes have longer laps or more complex cut patterns than others.

ASTM A615 plausibility warning

Warns when entered footage exceeds 50,000 linear feet, which often indicates a unit entry error (metres entered as feet). Prevents costly over-ordering mistakes.

Project-type presets

One-click presets for Residential, Commercial Mix, Bridge/Civil, and Target Weight load appropriate bar sizes, footage quantities, and pricing defaults.

Kg/m output for metric projects

All results include kilograms and kg/m values — essential for international projects, metric structural drawings, and suppliers quoting in SI units.

Print / Save PDF

Export a print-ready report of all inputs and results for purchase orders, RFQs, project bids, and site documentation.

How to Use the Rebar Weight Calculator

1
Select a project type preset — Residential, Commercial Mix, Bridge/Civil, or Target Weight — to load sensible defaults, or enter your own values.
2
Choose a calculation mode: Single bar size to convert one bar's footage to weight; Multi-bar mix for projects with multiple bar types; Target weight for reverse lookup from a spec or delivery quantity.
3
For Single mode: select your bar size (#3–#10), enter total linear footage, and set a waste percentage (10% is typical for most projects).
4
For Multi-bar mix: add a row for each bar size. Enter the net footage, stock bar length, and waste percentage for each. Add up to 6 bar types.
5
For Target weight mode: enter the weight from your structural spec or delivery manifest and select the bar size. Choose the unit — lbs, US tons, or kg.
6
Enter the stock bar length (default 20 ft) to get the exact number of bars to purchase. This rounds up to the nearest whole bar.
7
Optionally enter a price per US ton to generate a material cost estimate. Add a delivery or misc cost for a complete project total.
8
Press Calculate. Review the weight in lbs, US tons, and kg, bars to order, and the ASTM A615/A706 reference table with your active bar highlighted.
9
In multi-bar mode, review the per-bar breakdown showing each size's weight as a percentage of total steel — useful for procurement and logistics.
10
Use Print / Save to export a PDF of all inputs and results for RFQs, purchase orders, or project records.

Formulas Used in the Rebar Weight Calculator

1) Gross footage (with waste)Gross LF = Net LF × (1 + Waste % ÷ 100)
Waste covers lap splices, hook extensions, and off-cut trim. Use 10% for standard layouts; 15% for complex or heavily lapped designs.
2) Weight from footageWeight (lbs) = Gross LF × Unit Weight (lb/ft)
Weight (US tons) = Weight (lbs) ÷ 2,000
Weight (kg) = Weight (lbs) × 0.453592
Unit weights per ASTM A615/A706. Example: #5 bar = 1.043 lb/ft, so 500 ft = 521.5 lbs = 0.261 US tons.
3) Bars to orderBars = ⌈Gross LF ÷ Stock Bar Length⌉
Always rounded up to the next whole bar. A 20 ft stock bar is the most common standard length in North America.
4) Multi-bar total weightTotal Weight = Σ (Gross LF₍ᵢ₎ × Unit Weight₍ᵢ₎) for each bar size i
Each bar size uses its own gross footage (with its own waste factor) and its own unit weight from the ASTM table.
5) Reverse calculation (target weight → footage)Linear Footage = Target Weight (lbs) ÷ Unit Weight (lb/ft)
Converts a structural tonnage specification or delivery manifest weight back to the equivalent footage. Then rounds up to whole bars using stock length.
6) Unit conversions1 US ton = 2,000 lbs
1 lb = 0.453592 kg
1 metre = 3.28084 ft
All metric inputs are converted to imperial internally. Output is shown in all three weight units simultaneously.
7) Cost estimateMaterial Cost = Total Weight (US tons) × Price per Ton
Grand Total = Material Cost + Delivery / Misc Cost
Commercial rebar pricing is always quoted per US ton, not per bar or per linear foot. This matches standard steel supplier invoicing practice.

ASTM A615 / A706 Bar Weight Reference

All rebar weight values in this calculator are based on ASTM A615 (carbon steel) and ASTM A706 (low-alloy steel for weldability) published unit weights. Both standards specify identical theoretical unit weights for each bar size — the difference between A615 and A706 lies in chemistry and mechanical properties, not weight. The table below covers #3 through #10, which accounts for the overwhelming majority of concrete reinforcement applications.

Bar size	Diameter	Area (in²)	lb / ft	kg / m	Typical application
#3	0.375"	0.11	0.376	0.560	Ties, temperature steel, light flatwork
#4	0.500"	0.20	0.668	0.994	Driveways, patios, residential footings
#5	0.625"	0.31	1.043	1.552	Structural slabs, beams, columns
#6	0.750"	0.44	1.502	2.235	Heavy beams, retaining walls
#7	0.875"	0.60	2.044	3.042	Foundations, large retaining walls
#8	1.000"	0.79	2.670	3.973	Heavy columns, mat foundations
#9	1.128"	1.00	3.400	5.060	Bridge decks, transfer slabs
#10	1.270"	1.27	4.303	6.404	High-rise columns, heavy members

Weights are theoretical per ASTM A615/A706. Actual mill weights may vary ±3.5% for individual bars and ±3.5% for lots per ASTM tolerances. Always verify with certified mill test reports for structural applications.

Rebar Weight Quick Reference — Common Quantities

Use this table for quick estimates of common order quantities. Values include no waste factor — add 10–15% to all figures for a real procurement order.

100 ft of #3

37.6 lbs · 0.019 tons

Typical tie quantity, small footing

100 ft of #4

66.8 lbs · 0.033 tons

Small residential driveway section

500 ft of #4

334 lbs · 0.167 tons

Typical residential driveway

1,000 ft of #5

1,043 lbs · 0.522 tons

Medium structural slab

1 ton of #4

2,000 lbs · 1.000 ton

= 2,994 linear feet of #4

1 ton of #5

2,000 lbs · 1.000 ton

= 1,918 linear feet of #5

1 ton of #6

2,000 lbs · 1.000 ton

= 1,332 linear feet of #6

1 ton of #8

2,000 lbs · 1.000 ton

= 749 linear feet of #8

Values based on ASTM A615/A706 unit weights with no waste. Always add 10–15% for procurement orders.

Frequently Asked Questions

What is a rebar weight calculator?

A rebar weight calculator converts rebar linear footage to weight in lbs, US tons, and kg using published ASTM A615/A706 unit weights. It can also reverse the calculation — converting a target weight from a structural spec or delivery manifest back to the equivalent footage and bar count.

How much does rebar weigh per foot?

Rebar weight per foot depends on bar size per ASTM A615/A706: #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. These are theoretical unit weights; actual mill weights may vary ±3.5%.

How do I convert rebar linear footage to tons?

Multiply total linear footage by the unit weight in lb/ft for your bar size, then divide by 2,000 to convert to US tons. For example: 1,000 ft of #5 bar × 1.043 lb/ft = 1,043 lbs ÷ 2,000 = 0.522 US tons. Our calculator performs this conversion automatically for all bar sizes.

How do I convert rebar weight to linear footage?

Divide the weight in lbs by the unit weight in lb/ft for your bar size. For example: 2,000 lbs of #5 bar ÷ 1.043 lb/ft = 1,918 linear feet. This is the reverse calculation mode in our calculator — enter the weight in lbs, tons, or kg and select a bar size to get the equivalent footage.

What is the difference between ASTM A615 and ASTM A706 rebar?

Both standards specify identical unit weights for each bar size, so weight calculations are the same. The difference is in steel chemistry and mechanical properties: A615 is standard carbon-steel rebar used in most applications; A706 is a low-alloy steel with controlled chemistry for better weldability and ductility, required in seismic zones and applications where rebar must be welded.

Why is rebar priced per ton, not per bar?

Steel commodities — including rebar — are traded and priced by weight globally because weight is the fundamental measure of material content and production cost. A ton of #5 bar and a ton of #8 bar contain the same mass of steel, making per-ton pricing consistent across bar sizes. Our calculator converts your footage to tonnage so you can apply supplier per-ton quotes directly.

How many linear feet are in a ton of rebar?

It depends on bar size: #3 = 5,319 ft/ton, #4 = 2,994 ft/ton, #5 = 1,918 ft/ton, #6 = 1,331 ft/ton, #7 = 979 ft/ton, #8 = 749 ft/ton, #9 = 588 ft/ton, #10 = 465 ft/ton. Use the Target Weight mode in our calculator to reverse-calculate footage from any tonnage.

What waste percentage should I use for rebar weight calculations?

Use 10% for simple rectangular layouts with standard laps. Use 15% for complex layouts with many bends, hooks, or irregular shapes. The waste factor covers lap splice lengths (typically 40–60 bar diameters), hooks and bends, and off-cut trim from cutting to length. Waste increases gross footage, which increases the total weight and cost.

Can I calculate the weight of multiple bar sizes at once?

Yes. Switch to Multi-bar mix mode and add a row for each bar size. Enter the footage, stock length, and waste for each. The calculator produces individual weights per bar size — shown as a percentage of total steel — plus a combined total weight, tonnage, and bars to order.

What is a standard stock bar length for rebar?

In North America, 20-foot bars (6.1 m) are the most common standard stock length for #3 through #8 bars. Some suppliers also stock 30-foot (9.1 m) and 40-foot (12.2 m) lengths for larger projects. Our calculator lets you enter any stock length; it divides the gross footage by your stock length and rounds up to the nearest whole bar.

How accurate is the ASTM rebar weight table?

ASTM A615/A706 theoretical unit weights are highly accurate for estimation purposes. However, ASTM allows a ±3.5% weight tolerance per bar and ±3.5% per lot. This means a 1,000-lb order may actually weigh 965–1,035 lbs. For structural and certified-weight applications, always verify with mill test reports from your supplier.

Can I calculate rebar weight in metric units?

Yes. You can enter dimensions in metres and receive weight output in kilograms and kg/m values alongside imperial results. The Target Weight mode accepts weight in kg as well as lbs and US tons. All conversions use standard ASTM values: 1 lb = 0.453592 kg, 1 metre = 3.28084 ft.

Is the rebar weight calculator free?

Yes. The Rebar Weight Calculator on Concrete Calculator Max is completely free with no registration, subscription, or hidden fees. All three calculation modes — Single bar, Multi-bar mix, and Target weight reverse — are available at no cost.

Can I print or save my rebar weight estimate?

Yes. After calculating, press the Print / Save button to open a print-optimized report with all inputs and results. In your browser's print dialog, choose Save as PDF to keep a digital copy for purchase orders, RFQs, supplier quotes, or project records.

What is the rebar weight for a 20-foot bar?

It depends on bar size: #3 = 7.5 lbs, #4 = 13.4 lbs, #5 = 20.9 lbs, #6 = 30.0 lbs, #7 = 40.9 lbs, #8 = 53.4 lbs, #9 = 68.0 lbs, #10 = 86.1 lbs. These are the weights of a single standard 20-foot stock bar per ASTM A615/A706.

Related Calculators

Slab Concrete Calculator

Estimate concrete for floors, patios & driveways.

Try it now

Beam Concrete Calculator

Volume for rectangular or multi-span beams.

Try it now

Column Concrete Calculator

Round or rectangular column volumes in seconds.

Try it now

Footing Concrete Calculator

Strip & isolated footing volume estimates.

Try it now

Wall Concrete Calculator

Compute concrete for straight or segmented walls.

Try it now

Pier / Caisson Calculator

Drilled shaft & caisson concrete volumes.

Try it now

Tank / Trench Calculator

Rectangular & circular tank/trench volumes.

Try it now

Staircase Concrete Calculator

Total volume for flights, landings & risers.

Try it now

Nominal Mix (M5–M25)

Material splits for standard nominal mixes.

Try it now

Concrete Yards Calculator

Convert area/thickness into cubic yards & m³.

Try it now

Concrete Bag Calculator

Calculate how many concrete bags you need with unit conversions, bag sizes (40/50/60/80 lb & 20 kg), and waste buffers. Covers slabs, footings, posts, and sonotubes.

Try it now