How to Calculate a Cutting List for Aluminum Profiles (1D Cutting)

Q: How should I account for saw blade width (kerf)?

Measure your blade's actual cut width. When planning by hand, add it to every part length: with a 3 mm blade a 600 mm part uses 603 mm of the bar. Ignoring the blade on a bar with many cuts can make the last piece come out short. In CutOptimizer you simply set the saw blade width and every plan accounts for it automatically.

Q: How do I calculate waste percentage?

Waste % = (total stock length used - total finished part length) / total stock length used x 100. Example: 3 bars of 6000 mm = 18000 mm, parts = 17700 mm, waste = 300 mm, so waste is 1.67%.

Q: Is there software that calculates a cutting list automatically?

Yes. CutOptimizer is an offline Windows app on the Microsoft Store that imports stock and demand lists from Excel, lets you set your saw blade width (kerf), calculates 1D cutting plans in fast heuristic or exact mode, draws a visual diagram for each stock piece, and exports a PDF worksheet. It is a $29.99 one-time purchase with a free trial.

The problem: many parts, fixed-length bars

Aluminum profiles usually come in fixed stock lengths such as 6000 mm (about 20 ft). A window, door, or frame order is a list of part lengths and quantities. The question is always the same: how do I cut these parts from as few bars as possible, with the least scrap?

This is called the one-dimensional (1D) cutting stock problem. Only length matters, so you do not need CAD. You need a clear method. The same method works for steel tube, pipe, trim, and lumber.

A worked example

Say you have 6000 mm profile bars, a saw blade that removes 3 mm per cut, and this order:

Part length	Quantity	Total length
2400 mm	4	9600 mm
1600 mm	3	4800 mm
600 mm	3	1800 mm
500 mm	3	1500 mm
Total	13 parts	17700 mm

Step 1: Find the minimum number of bars

Add one blade width for every part (a simple, safe rule), then divide by the stock length:

17700 mm + 13 × 3 mm = 17739 mm
17739 ÷ 6000 = 2.96 → at least 3 bars

No plan can use fewer than 3 bars. Now we check whether 3 is actually possible.

Step 2: What happens if you cut in list order

A common habit is to cut parts in the order they appear on the sheet (here, shortest first) and start a new bar when the next part does not fit. With 3 mm added to each part, that gives:

Bar 1: 500, 500, 500, 600, 600, 600, 1600 → offcut 1079 mm

Bar 2: 1600, 1600, 2400 → offcut 391 mm

Bar 3: 2400, 2400 → offcut 1194 mm

Bar 4: 2400 → offcut 3597 mm

That is 4 bars (24000 mm of stock) for 17700 mm of parts.

Step 3: Use first-fit decreasing

First-fit decreasing (FFD) is the classic manual method:

Sort all parts from longest to shortest, and add the blade width to each: 2403, 1603, 603, 503 mm.
Take the next part and put it into the first bar that still has room for it.
Open a new bar only if no open bar has room.

Walking through it:

The four 2400 parts: two go into Bar A (4806 mm used), two into Bar B (4806 mm). Each has 1194 mm left, so neither can take a third 2400.
The three 1600 parts do not fit in A or B (1194 mm left), so they open Bar C: 3 × 1603 = 4809 mm used, 1191 mm left.
600 parts: the first goes into A (591 mm left). The second does not fit in A (needs 603), so it goes into B (591 mm left). The third goes into C (588 mm left).
500 parts: one each into A, B, and C, since each has at least 503 mm left.

Bar A: 2400 + 2400 + 600 + 500 = 5900 mm parts, 12 mm kerf, offcut 88 mm

24002400600500

Bar B: 2400 + 2400 + 600 + 500 = 5900 mm parts, 12 mm kerf, offcut 88 mm

24002400600500

Bar C: 1600 + 1600 + 1600 + 600 + 500 = 5900 mm parts, 15 mm kerf, offcut 85 mm

160016001600600500

Same order, 3 bars instead of 4. Since Step 1 showed that 3 is the minimum, this plan cannot be beaten on bar count.

Step 4: Calculate waste percentage

Waste % = (stock used − finished parts) ÷ stock used × 100

Method	Bars	Stock used	Waste (offcuts + kerf)	Waste %
List order	4	24000 mm	6300 mm	26.25%
First-fit decreasing	3	18000 mm	300 mm	1.67%

In the FFD plan, the 300 mm of waste is 39 mm of saw kerf (13 cuts × 3 mm) plus 261 mm of offcuts (88 + 88 + 85). You save a full 6 m bar on a 13-part order.

Tips for accurate cutting lists

Measure your real blade width. Use the actual kerf of the blade on your saw, not a guess, whether you plan by hand or enter it in software. On a bar with many short parts, a few millimeters per cut adds up.
Allow for end trimming. If you square off the factory end of each bar, subtract that trim from the usable length (for example, plan with 5980 mm instead of 6000 mm).
Cut long parts first. Long parts are the hardest to place. Short parts are best used to fill the gaps at the end of a bar.
Decide what counts as a usable remnant. An offcut of 1 m may be worth keeping; 85 mm usually is not. Set a minimum and label remnants you keep.
Check the lower bound. Total length ÷ stock length tells you quickly whether a plan can still be improved.
Double-check angles. For mitered frame parts, make sure your list uses the long-point length your saw setup expects.

Let CutOptimizer do the math

FFD by hand is fine for 13 parts. For a real job with dozens of lengths and several orders, it becomes slow and easy to get wrong. CutOptimizer is a Windows desktop app that does this planning for you:

Import from Excel. Load your stock and demand lists from a spreadsheet instead of retyping them.
Saw blade width (kerf) setting. Set your blade width and every plan allows for it automatically, so you no longer add it to each part by hand.
Fast heuristic or exact mode. Get a quick plan in seconds, or switch to exact mode when you want the best plan it can find.
Visual cutting diagrams. See a colorful diagram for every stock piece, like the bars above.
PDF worksheets. Export a clean PDF for the shop floor so the operator cuts exactly what was planned.
Offline and private. Projects stay on your PC, and there is no monthly subscription.
11 languages, Windows 10 and Windows 11.

$29.99 one-time purchase, with a free trial. Try it on your next order list and compare the result with your current plan.

Get CutOptimizer on Microsoft Store

FAQ

How do I calculate how many bars of stock I need?

Add up all part lengths, add one blade width for every cut, and divide by the stock length. Round up to get the minimum number of bars. A real plan may need more, because pieces must fit into whole bars.

What is first-fit decreasing in cutting optimization?

Sort parts from longest to shortest, then place each part into the first bar that still has room. Open a new bar only when no existing bar has room. It is easy by hand and usually beats cutting in list order.

How should I account for saw blade width (kerf)?

Measure your blade's actual cut width. By hand, add it to every part length: with a 3 mm blade, a 600 mm part uses 603 mm of the bar. In CutOptimizer you just set the saw blade width and every plan includes it automatically.

How do I calculate waste percentage?

(Stock used − finished parts) ÷ stock used × 100. Example: 3 bars × 6000 mm = 18000 mm, parts = 17700 mm, waste = 300 mm, so 1.67%.

Is there software that calculates a cutting list automatically?

Yes. CutOptimizer imports stock and demand lists from Excel, lets you set your saw blade width (kerf), calculates 1D cutting plans in fast heuristic or exact mode, shows a diagram for each stock piece, and exports a PDF worksheet. It is $29.99 one-time on the Microsoft Store, with a free trial.