# Steel, Aluminum Plate and Bar Weight Calculator

> Source: https://netray.co/tools/steel-aluminum-plate-and-bar-weight-calculator
> Publisher: Netray (netray.co), AI and integration engineering for ERP and manufacturing systems.
> Section: Free Tools

## Short answer

Weight and material cost of plate, round bar, square bar and hex bar in common metals, with kg per metre and a thickness sweep chart.

## Category

engineering-plm

## Audience

- Buyer
- Estimator
- Design engineer
- Cost accountant

## Tool

**Kind:** calculator

**Currency:** $

**Inputs:**

#### Material

**Key:** density

**Type:** select

**Default:** 7.85

**Options:**

##### Carbon steel (7.85 g/cm3)

**Value:** 7.85

##### Stainless 304 (7.93 g/cm3)

**Value:** 7.93

##### Stainless 316 (8.00 g/cm3)

**Value:** 8

##### Aluminum 6061 (2.70 g/cm3)

**Value:** 2.7

##### Copper (8.96 g/cm3)

**Value:** 8.96

##### Brass (8.50 g/cm3)

**Value:** 8.5

##### Titanium Grade 5 (4.43 g/cm3)

**Value:** 4.43

##### Grey cast iron (7.20 g/cm3)

**Value:** 7.2

**Help:** Nominal density. Use the mill certificate value for exact stock.

#### Shape

**Key:** shape

**Type:** select

**Default:** 1

**Options:**

##### Plate or flat (width x thickness)

**Value:** 1

##### Round bar (diameter)

**Value:** 2

##### Square bar (side)

**Value:** 3

##### Hex bar (across flats)

**Value:** 4

#### Width, diameter or side

**Key:** dim_a

**Type:** number

**Default:** 1000

**Min:** 0

**Step:** 1

**Unit:** mm

**Help:** Plate width, round diameter, square side or hex across-flats size.

#### Plate thickness

**Key:** dim_b

**Type:** number

**Default:** 10

**Min:** 0

**Step:** 0.5

**Unit:** mm

**Help:** Used for plate and flat only. Ignored for bar shapes.

#### Length

**Key:** length

**Type:** number

**Default:** 2000

**Min:** 0

**Step:** 10

**Unit:** mm

#### Quantity

**Key:** qty

**Type:** number

**Default:** 4

**Min:** 0

**Step:** 1

**Unit:** pcs

#### Material price

**Key:** price

**Type:** number

**Default:** 1.2

**Min:** 0

**Step:** 0.05

**Unit:** per kg

**Help:** Optional. Leave at your quoted price per kg to get a cost estimate.

**Outputs:**

#### Cross-section area (mm2)

**Key:** area

**Expr:** if(eq(shape,1), dim_a * dim_b, if(eq(shape,2), pi * dim_a * dim_a / 4, if(eq(shape,3), dim_a * dim_a, 0.8660254 * dim_a * dim_a)))

**Format:** decimal

**Description:** Plate: width x thickness. Round: pi x d squared / 4. Square: side squared. Hex: 0.866 x across-flats squared.

#### Weight per metre (kg/m)

**Key:** kg_m

**Expr:** area * density / 1000

**Format:** decimal

#### Weight per piece (kg)

**Key:** unit_kg

**Expr:** area * length * density / 1000000

**Format:** decimal

**Primary:** true

#### Total weight (kg)

**Key:** total_kg

**Expr:** unit_kg * qty

**Format:** decimal

**Primary:** true

#### Total weight (lb)

**Key:** total_lb

**Expr:** total_kg * 2.2046226

**Format:** decimal

#### Material cost

**Key:** cost

**Expr:** total_kg * price

**Format:** currency

**Chart:**

#### Total weight vs plate thickness

**Type:** line

**X:** dim_b

**From:** 5

**To:** 50

**Steps:** 20

**Series:**

- total_kg

**Disclaimer:** Theoretical weight from nominal density and nominal dimensions. Mill tolerances, corner radii, rolling margin and kerf are not included.

## Content

**Intro:** This calculator returns the theoretical weight of plate, flat, round bar, square bar and hex bar in the metals buyers and estimators quote every day. It also gives kg per metre, which is the number most mill price lists and ERP item masters use.

**Sections:**

#### How to use the calculator

**Body:** Pick the material, then the shape. For plate or flat enter width and thickness; for bars enter the single size (diameter, side or across-flats) and leave thickness alone. Enter piece length and quantity to get piece weight, total weight in kg and lb, and a cost line if you type your price per kg. The chart sweeps plate thickness from 5 to 50 mm so you can see how fast weight and cost climb when a drawing moves to the next standard gauge.

**Bullets:**

- All dimensions are in millimetres, density in g/cm3
- Thickness is ignored for round, square and hex bar
- Use the cost field for quick RFQ comparisons, not for final quotes
- Change quantity to see order weight for freight planning

#### The formula behind the result

**Body:** Weight equals volume times density. With dimensions in mm and density in g/cm3, weight in kg is area (mm2) x length (mm) x density / 1,000,000. Areas are width x thickness for plate, pi x d squared / 4 for round, side squared for square, and 0.866 x AF squared for a regular hexagon. A 20 mm round steel bar has an area of 314 mm2, so at 7.85 g/cm3 it weighs about 2.47 kg per metre, which matches published bar tables.

#### Worked example and how to read it

**Body:** A 1000 x 10 mm carbon steel plate cut to 2000 mm has an area of 10,000 mm2 and weighs 157 kg per piece; four pieces are 628 kg, about 1,384 lb. Compare that against the mill certificate or the weigh-bridge ticket. Rolled plate is commonly a few percent heavier than theoretical because thickness tolerance is usually positive-biased, so buyers often accept up to roughly 3 to 5 percent variance between theoretical and weighed mass.

#### Common mistakes and ERP notes

**Body:** The usual errors are mixing inches and millimetres, using the wrong density for stainless or aluminum, and forgetting that hex size is across flats, not across corners. In an ERP, store the weight per unit of measure on the item master (SAP gross and net weight on the material master, SyteLine item weight, Epicor part weight) so freight, costing and shipping documents agree with what you quote here.

**Bullets:**

- Do not use steel density for aluminum or stainless
- Hex across corners is about 1.155 times across flats
- Cut loss and offcuts are not in theoretical weight
- Check your ERP weight unit of measure before loading

**Cta:** If your item master weights are wrong or missing, Netray can help build a read-only check that compares ERP weights with calculated values. Ask for a short review.

**Faq:**

#### What is the weight of a steel plate per square metre?

**Answer:** For carbon steel at 7.85 g/cm3, weight is 7.85 kg per square metre per millimetre of thickness. A 10 mm plate is about 78.5 kg per square metre, and a 20 mm plate is about 157 kg per square metre.

#### How do I calculate round bar weight per metre?

**Answer:** Multiply diameter squared (in mm) by 0.006165 for carbon steel to get kg per metre. This is pi / 4 x 7.85 / 1000. For aluminum 6061 use 0.002121, since the density is 2.70 g/cm3.

#### Is theoretical weight the same as actual weight?

**Answer:** Not exactly. Mill tolerances on thickness, width and length mean actual weight differs from nominal by a few percent. Contracts usually state whether you pay on theoretical or weighed mass, so confirm before comparing invoices.

#### Which density should I use for stainless steel?

**Answer:** Use about 7.93 g/cm3 for austenitic 304 and about 8.00 g/cm3 for 316. Ferritic and martensitic grades such as 430 and 410 are closer to 7.70 to 7.75 g/cm3. Check the datasheet for duplex and precipitation grades.

## Search terms

steel plate weight calculator, aluminum plate weight calculator, round bar weight calculator, metal weight calculator, steel bar weight per metre, hex bar weight formula, stainless steel plate weight, kg per metre steel bar

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