Steel Plate Cutting Optimizer & Waste Calculator
This free plate cutting optimizer works out the best way to cut your parts from standard steel plates. Enter the master plate size and the sizes you need. It nests the pieces, draws the cutting layout for every plate, and shows how many plates to buy, the waste %, the scrap weight in kg and the cost of the wasted steel.
Key facts
- Waste % = (total plate area − area of the cut pieces) ÷ total plate area × 100.
- Steel plate weight (kg) = length (m) × width (m) × thickness (mm) × 7.85.
- Scrap cost = scrap weight (kg) × price per kg.
- Guillotine cutting uses straight cuts from edge to edge, so it suits shears and saws. Free nesting (MaxRects) packs tighter and suits laser, plasma and CNC cutting.
- Most steel plate jobs waste 10–30% when they are well nested.
Open the optimizer full screen
How to plan plate cutting with the least waste
- Choose the master plate. Pick a standard size such as 3000 × 1500 mm or 6000 × 2000 mm, or type your own. Then enter the thickness.
- Add the cut sizes. Enter the length, width and quantity of every part. Sizes can be in mm or metres.
- Set the cutting details. Enter the saw kerf (the width the blade or torch removes), any edge trim, and whether parts may rotate. Turn rotation off if the grain or pattern direction matters, for example on chequered plate.
- Choose the cutting method. Use Guillotine for shear or saw cutting, Free nesting for laser or plasma, or Best result to try both.
- Read the result. Check the plates needed, the waste % and the scrap cost. Then print the layout or save it as a PDF, download the cut list as CSV, or send it to us on WhatsApp for a plate price.
How the optimizer works
Fitting rectangles onto plates is called 2D bin packing. A perfect answer takes too long to compute for real jobs, so the optimizer uses two proven fast methods:
- Guillotine: each part goes into the smallest free area that holds it, and the leftover space is split by a full-length cut. Every cut runs straight across a plate or strip, so a guillotine shear or panel saw can make it.
- MaxRects free nesting: the optimizer keeps a list of all the free rectangles on each plate and places each part where it leaves the shortest leftover side. Parts can sit in any position, which usually saves more steel when the parts are cut by laser, plasma or CNC.
In Best result mode it runs both methods with four different sort orders, with and without rotation (up to 16 plans). It then keeps the plan that needs the fewest plates and leaves the biggest usable offcut on the last plate. Identical plates are grouped, so a large job shows only the different layouts.
Worked example
You need 12 pieces of 700 × 500 mm from a 3000 × 1500 × 10 mm MS plate, with no kerf.
- The plate is 4.5 m² and weighs 3 × 1.5 × 10 × 7.85 = 353.25 kg.
- The plate takes 4 pieces along the 3000 mm length and 3 across the 1500 mm width, so all 12 pieces fit on 1 plate.
- The pieces use 12 × 0.35 = 4.2 m², so the scrap is 0.3 m² and the waste is 6.7%.
- The scrap weighs 0.3 × 10 × 7.85 = 23.55 kg. At AED 3.35 per kg, the wasted steel costs AED 78.89.
Standard steel plate sizes and weights
| Plate size (mm) | Area (m²) | kg per mm thickness | 3 mm | 6 mm | 10 mm | 12 mm |
|---|---|---|---|---|---|---|
| 2440 × 1220 (8 × 4 ft) | 2.977 | 23.37 | 70.1 | 140.2 | 233.7 | 280.4 |
| 2500 × 1250 | 3.125 | 24.53 | 73.6 | 147.2 | 245.3 | 294.4 |
| 3000 × 1500 | 4.500 | 35.33 | 106.0 | 211.9 | 353.3 | 423.9 |
| 6000 × 1500 | 9.000 | 70.65 | 211.9 | 423.9 | 706.5 | 847.8 |
| 6000 × 2000 | 12.000 | 94.20 | 282.6 | 565.2 | 942.0 | 1,130.4 |
Weights are theoretical MS plate weights in kg at 7,850 kg/m³. For any other size, use the MS plate weight calculator.
7 ways to reduce steel plate waste
- Choose the plate size that fits your parts best. Try 3000 × 1500, 6000 × 1500 and 6000 × 2000 in the optimizer and compare the waste %.
- Let parts rotate when grain direction does not matter.
- Combine several jobs of the same thickness on one plate.
- Put large parts first and fill the gaps with small parts. The optimizer does this for you.
- Enter the real kerf. Plasma removes about 2–4 mm and a saw blade 2–3 mm. Laser removes less than 1 mm.
- Keep large offcuts with their size marked on them, and use them for brackets, gussets and base plates.
- Order cut-to-size plate when you need few parts. It can cost less than buying a full plate and scrapping half of it.
Frequently asked questions
How do I calculate steel plate cutting waste?
Add up the area of all the cut pieces and subtract it from the total area of the plates used. Divide the difference by the total plate area and multiply by 100 to get the waste %. Multiply the scrap area (m²) by the thickness (mm) and 7.85 to get the scrap weight in kg.
How many pieces can I cut from one steel plate?
For identical pieces, divide the plate length by the piece length and the plate width by the piece width, round both down, and multiply. A 3000 × 1500 mm plate gives 4 × 3 = 12 pieces of 700 × 500 mm. For mixed sizes, use the optimizer above.
What is the difference between guillotine and nesting cutting?
Guillotine cutting uses only straight cuts from one edge to the other, as a shear or panel saw needs. Nesting places parts anywhere on the plate and is used with laser, plasma and CNC machines. Nesting usually wastes less steel.
What is kerf, and why does it matter?
Kerf is the width of material the blade, torch or laser removes. Each cut loses that much steel, so the optimizer adds the kerf to every piece. With many small parts it can change the number of plates you need.
What is a normal waste percentage for steel plate?
Well-nested plate work usually wastes 10–30%. Jobs with few large parts, or parts that do not match the plate size, can waste much more. A large offcut on the last plate can be kept for other jobs.
Can I use this for aluminium or stainless steel plate?
Yes. Choose stainless 304 (7,930 kg/m³) or aluminium (2,700 kg/m³) as the material, and the weights and scrap cost change to match. The cutting layout stays the same.
Can I save or print the cutting layout?
Yes. Click Export PDF / Print plan and choose Save as PDF. You can also download a CSV cut list with the plate number and X/Y position of every piece.
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Buy steel plate in the UAE
Ibnee Younus Building & Construction Materials Trading Co. LLC supplies MS plate, chequered plate, GI sheet and aluminium chequered plate in standard sizes from Dubai Industrial City, Dubai, open every day from 8 AM to 7 PM. Send your cutting plan for today’s plate price and stock. See our MS plate supplier page.