I Beam Weight Calculator

Updated Aug 4, 2026 By Jehan Wadia

Introduction

The I Beam Weight Calculator tells you how much a steel I-beam weighs. Pick a standard profile like IPE, HW, HM, HN, HP, or a hot rolled I-beam, then enter the length. You can also type your own sizes: height (H), flange width (B), web thickness (t₁), flange thickness (t₂), and fillet radius (r).

The tool shows the total weight in kilograms, pounds, metric tons, and grams. It also gives you the weight per meter, the cross-sectional area, and the section perimeter. You can change the material too, from mild steel to aluminum, copper, brass, and more. For other shapes, try the broader Steel Weight Calculator or the general Metal Weight Calculator.

You get a scaled drawing of the beam cross-section, a step-by-step math solution, and charts that split the weight between the web, the flanges, and the fillets. Use it to plan steel orders, check shipping loads, guess crane lifts, or price a job before you buy.

How to use our I Beam Weight Calculator

Pick a standard beam or type your own beam sizes, add the length and material, and the calculator gives you the total weight in kg, lbs, tons, and grams, plus the weight per meter, cross-section area, perimeter, a scaled diagram, and the full math.

Standard Profile Lookup or Custom Manual Input: Use the top tabs. Choose "Standard Profile Lookup" to use a catalog beam size. Choose "Custom Manual Input" to type your own I beam dimensions.

Beam Category: Pick the beam family you are using, like IPE, H-beam (HW, HM, HN, HP), ordinary hot rolled, or light duty. This changes the list of profiles below it.

Profile / Specification: Pick the exact beam size. Each option shows the real height, flange width, web thickness, flange thickness, and fillet radius in mm.

Height (H): In custom mode, type the total depth of the beam from the top flange to the bottom flange. Pick mm, cm, m, in, or ft. If your drawings are in inches, the Inches To Mm Calculator helps you switch fast.

Flange Width (B): Type how wide the top and bottom flanges are, and pick the unit.

Web Thickness (t₁): Type how thick the upright middle plate (the web) is. It must be smaller than the flange width.

Flange Thickness (t₂): Type how thick each flange plate is. Two flanges together must be smaller than the height.

Fillet / Root Radius (r): Type the curved corner size where the web meets the flange. Leave it as 0 for a plain welded beam.

Length (L): Type how long one beam is and pick mm, cm, m, in, or ft. To convert stock lengths, see the Meters to Feet Calculator.

Material (density): Pick the metal, such as mild steel, stainless steel, or aluminum. The density in kg/m³ is used to work out the weight. You can look up or check any value with the Density Calculator.

Number of Pieces: Type how many beams of this same size you need. The total weight is multiplied by this number.

Show dimensions in: Pick the unit used for the labels on the cross-section diagram and the read-only size boxes.

Chart weight unit: Pick kg, lbs, t, or g for the weight breakdown chart and the material comparison chart. The Kg To Lbs Calculator is handy if a supplier quotes in pounds.

Calculate and Reset: Results update as you type, but you can press Calculate to refresh them. Press Reset to go back to the starting values.

I Beam Weight: What It Is and Why It Matters

An I beam is a steel bar shaped like the letter I. It has two flat plates called flanges (top and bottom) and a thin upright part in the middle called the web. This shape is strong but uses less steel than a solid block, so builders use I beams for floors, roofs, bridges, and frames.

The Parts of an I Beam

Height (H) — how tall the beam is from the top flange to the bottom flange.
Flange width (B) — how wide the top and bottom plates are.
Web thickness (t₁) — how thick the middle upright part is.
Flange thickness (t₂) — how thick each flat plate is.
Fillet radius (r) — the small curved corner where the web meets each flange. Rolled beams have this curve, so it adds a bit of extra steel.

How I Beam Weight Is Found

Weight comes from three things: the shape of the cut end (the cross-sectional area), the length, and the density of the metal.

Area = H × t₁ + 2 × B × t₂ − 2 × t₁ × t₂ + (4 − π) × r²

The first part is the web, the second part is both flanges, and the third part is taken away so the spot where the web and flange meet is not counted twice. The last part adds the small fillet corners.

Weight = Area × Length × Density

Mild steel has a density of about 7850 kg/m³. So a beam with an area of 0.0028 m², a length of 6 m, and steel density gives about 132 kg. The same area figure feeds into stiffness checks, so pair this tool with the Section Modulus Calculator and the Moment of Inertia Calculator.

Weight Per Meter

Steel sellers often list beams by weight per meter (kg/m) or weight per foot (lb/ft). This number stays the same no matter how long the beam is, so it is an easy way to compare sizes. Multiply it by the length to get the full weight, or use the Linear Feet Calculator when you are ordering by run length.

Common Beam Types

IPE beams are the European standard sizes. H-beams come in HW (wide flange), HM (medium flange), HN (narrow flange), and HP (steel piles) series. Ordinary and light hot rolled I-beams are common in Asia. Each type has set dimensions listed in steel tables, so you only need the name and length to get the weight.

Why Beam Weight Is Useful

Cost — steel is sold by weight, so weight sets the price.
Shipping — trucks and cranes have weight limits. Check the billed weight with the Volumetric Weight Calculator and the Freight Class Calculator.
Design — the beam's own weight is a load the structure must hold, so it belongs in your Beam Deflection Calculator and Beam Calculator checks, along with any wind load on the frame.
Painting — the perimeter tells you how much surface needs coating or fireproofing; the Paint Calculator turns that area into cans.
Connections — heavier sections need bigger bolts, so run the Bolt Torque Calculator before assembly.

Different Metals, Different Weight

The same beam shape weighs very different amounts in other metals. Aluminum is about one third the weight of steel, as the Aluminum Weight Calculator shows. Lead is much heavier. Only the density changes in the math — the shape stays the same.

Related Steel and Structure Tools

Working out a full material list? These calculators cover the rest of the package: Plate Weight Calculator, MS Plate Weight Calculator, Sheet Metal Weight Calculator, Square Tube Weight Calculator, Tube Weight Calculator, Pipe Weight Calculator, Rebar Calculator, Truss Calculator, Floor Joist Calculator, Framing Calculator, and the Concrete Weight Calculator for the slab the steel sits on.

Formulas used

Cross-sectional area of the I-beam (with fillet correction)

A = H t_1 + 2 B t_2 - 2 t_1 t_2 + (4-\pi) r^2

Section perimeter (surface area per unit length)

P = 4B + 2H - 2t_1 - (8-2\pi) r

Weight per metre

w = A \times \rho

Total weight of all pieces

W = A \times \rho \times L \times n

Component weights (web, two flanges, fillets)

W_{web} = (H - 2t_2) t_1 L \rho n,\quad W_{flanges} = 2 B t_2 L \rho n,\quad W_{fillets} = (4-\pi) r^2 L \rho n

Weight unit conversions

W_{lb} = \frac{W_{kg}}{0.45359237},\quad W_{t} = \frac{W_{kg}}{1000},\quad W_{g} = W_{kg} \times 1000

Length unit conversion to metres

x_{m} = x \times k,\quad k \in \{0.001,\ 0.01,\ 1,\ 0.0254,\ 0.3048\}

Frequently asked questions

Why is my answer slightly different from the steel mill's catalog weight?

Catalog weights come from rolling standards and are rounded. This tool uses the exact shape math with the fillet corners added. The gap is usually under 2%.

Real beams also vary a little in thickness, so the shipped weight can differ from any theoretical number.

Do I have to enter the fillet radius?

No. Leave it at 0 for a plate beam that is welded together, since welded beams have sharp corners.

For a hot rolled beam, put in the radius from the steel table. It adds a small amount of steel, often 1% to 3% of the total.

Can I mix units, like mm for the beam size and feet for the length?

Yes. Each box has its own unit menu. You can set H, B, t₁ and t₂ in mm and set the length in feet.

Everything is changed to meters inside the tool before the math runs, so the result is still correct.

Can I use this for American W shapes or S beams?

Yes, use the Custom Manual Input tab. Type the height, flange width, web thickness, flange thickness and fillet radius from your W or S table.

S beams have sloped flanges, so the answer will be a close estimate, not exact.

Why are the dimension boxes locked in Standard Profile mode?

Those sizes come straight from the steel tables, so they stay read-only to stop typing mistakes.

If you need to change a number, switch to the Custom Manual Input tab and type your own values.

What does the spec notation like 200×100×5.5×8 mean?

It is a short way to write the beam size in millimeters. The order is height × flange width × web thickness × flange thickness.

Steel yards use this code on quotes and packing lists.

Does the weight include bolt holes, cuts, or end plates?

No. The tool gives the weight of a plain, full-length beam.

Holes and cuts take weight off. Base plates, stiffeners and welds add weight. Add or subtract those parts on your own.

Does paint or galvanizing change the weight?

A little. Hot dip galvanizing usually adds about 3% to 6% of the steel weight.

Paint adds much less. Use the section perimeter result to work out the coated surface area per meter.

How do I get the weight in pounds per foot?

Look at the Section Properties card. Under Weight per Meter, the small grey line shows the same value in lb/ft.

You can also set the chart unit to lbs to see totals in pounds.

Why does the formula subtract 2 × t₁ × t₂?

The web part of the math runs the full height of the beam, including the bit inside each flange.

The flange part counts that same bit again. Taking away 2 × t₁ × t₂ removes the double count so the area is right.

What is the donut chart showing me?

It splits the total weight into three parts: the web, the two flanges, and the fillet corners.

On most I beams the flanges hold more than half the steel. This helps when you compare a wide flange to a narrow one.

Why did I get an error saying the web must be smaller than the flange width?

The web sits inside the flanges, so t₁ has to be less than B. Also, two flange thicknesses must be less than the height H.

If you see this error, check that you did not mix up a unit, like typing cm in a mm box.

Can I work out the price of my steel order with this?

Yes, in two steps. Get the total weight, then multiply it by your price per kg or per ton.

Set the number of pieces first so the total covers the whole order.

Does this tell me how much load the beam can hold?

No. This tool only gives weight, area and perimeter.

For strength and bending, you need the section modulus and moment of inertia, plus the span and load. Use a beam design tool for that.

How accurate is this calculator?

The math is exact for the sizes you enter. The area, perimeter and weight are all worked out to full precision, then rounded for display.

Real world weight can still shift by 1% to 3% because of rolling tolerance on thickness.

Which beam should I pick if I only know the depth, like 200 mm?

Many families have a 200 mm deep beam: IPE 200, HN 200×100, HW 200×200 and ordinary 20a. They all weigh different amounts.

Check your drawing or supplier note for the family name, then match the flange width to be sure.

Can I change the unit shown on the diagram?

Yes. Use the Show dimensions in menu above the drawing. Pick mm, cm, m, in or ft.

The labels on the picture and the read-only size boxes both switch to that unit right away.

Why is the total weight the same when I change only the number of pieces?

It should not be. Check that you typed a whole number of 1 or more in the Number of Pieces box.

The card header also shows the per-piece weight when you order more than one.