Compare your current insert with a newly proposed turning or milling insert — not only by purchase price, but by usable cutting edges, tool life, cycle time, downtime, scrap rate and machine hourly cost.
1. Select the operation type
2. Production and shop data
3. Current and new cutting tool data
Enter tool life values for the same workpiece, the same quality requirement and, as far as possible, the same trial conditions.
Current Tool (A)
Advanced quality and investment data
New Tool (B)
Advanced quality and investment data
4. Cutting tool comparison result
| Calculated value | Tool A | Tool B |
|---|---|---|
| Effective usable edges | — | — |
| Tooling cost / produced part | — | — |
| Cycle cost / produced part | — | — |
| Downtime cost / produced part | — | — |
| Cost incl. scrap effect / good part | — | — |
| Total annual production time | — | — |
| Annual tooling consumption cost | — | — |
| Annual operation cost | — | — |
| First-year total (incl. investment) | — | — |
Why should inserts never be compared on price alone?
A cheap insert does not always mean a low cost per part. The true impact of a cutting tool must be evaluated together with the parts machined per edge, the edges actually usable, the cycle time, machine stoppages during edge indexing and insert changes, quality loss and scrap rate.
A new insert may cost more yet reduce the annual total cost if it delivers longer life, shorter cycles and fewer unplanned stops. Conversely, an insert running at aggressive cutting data may produce faster but wipe out the expected gain if it degrades surface finish or drives up scrap.
Core cost formulas used in this calculation
What to compare for turning inserts
- Insert price and the number of edges genuinely usable
- Good parts machined with one edge
- Change in cycle time and the machine hourly rate
- Time for edge indexing, insert changes and offset checks
- Surface finish, tolerance, chip control and scrap rate
Cutting speed, feed and depth of cut do not affect tool life equally. Cutting speed in particular can change tool life dramatically. When trialling two inserts, record not only the part count but also the cutting data used and the quality achieved.
How is milling insert cost calculated?
In milling, all inserts in the body cut together, so the insert count directly drives tooling consumption cost. That is why the “number of inserts in the milling body” field appears in this calculator. If all inserts are indexed together when an edge reaches end of life, enter the indexing time and insert count for the same tool set.
Milling efficiency is not limited to tool life. Feed per tooth, effective tooth count, table feed, width of cut and depth of cut set the cycle time; tool clamping, overhang and machine stability drive vibration and quality.
Interpreting the result correctly
This tool compares two cutting tools against each other. To work out the total machining cost per part, including machine hours and auxiliary times, use the CNC Machining Cycle Time and Cost per Part Calculator.
- Annual savings: The total operation cost difference between the two tools for the same quantity of good parts.
- Capacity gain: Machine hours freed up by shorter cycles and less downtime.
- Break-even hourly rate: The machine rate above which the expensive-but-fast tool becomes the economic choice.
- Return on investment: How many parts or months it takes to recover the cost of a new tool body or holder.
Frequently asked questions
Should I enter tool life in minutes or parts?
This tool works on a parts-per-edge basis. Enter the average number of good parts machined with one edge. If you track tool life in minutes, divide the tool life minutes by the average cycle time to estimate parts per edge.
My milling body holds eight inserts — should I multiply the price by eight?
No. Enter the price of a single insert in “Price of one insert” and write eight in “number of inserts in the milling body”. The calculator works out the tool set cost itself.
Why is there an edge utilization rate?
On some inserts, tool orientation, clamping, damage or unplanned breakage means not every catalogue edge can actually be used. The real utilization rate stops the results from being inflated.
Is the result reliable if I don't know the machine hourly cost?
The tool still shows tooling consumption and the time difference, but it will not declare a single “more profitable tool”. A monetary decision requires an approximate machine hourly cost covering labor, energy, depreciation and overhead.