What unit cost should I use for scrapped parts?

Use the accumulated cost at the operation where the part failed, not just raw material. A blank scrapped before machining might carry $4 of material, but the same part scrapped after three operations may carry $22 in material, labor, and machine time. Costing scrap at its stage captures the true loss and correctly prioritizes downstream defects, which are always more expensive to throw away.

How do I calculate scrap rate as a percentage?

Divide scrapped quantity by total quantity produced over the same period. If a line runs 12,000 units and scraps 240, the scrap rate is 2.0 percent. For financial reporting, divide scrap cost by output value instead: $8,600 of scrap against $430,000 of production is 2.0 percent of output value. Track both, since a low piece rate can still be costly if the scrapped parts are high-value.

What is a good scrap rate benchmark for manufacturing?

It varies by process. Machining and assembly often target under 1 to 2 percent, while casting, molding, and stamping may accept 3 to 5 percent early in a run. World-class operations push scrap below 1 percent. Rather than chase an industry number, baseline your own line, then set a reduction goal such as cutting the current 3.2 percent to 2.0 percent within a quarter.

How do I build a Pareto chart from scrap data?

Sum scrap cost by defect code, sort descending, then compute a running cumulative percentage. Typically the top 2 or 3 codes account for about 80 percent of cost. If porosity is $4,200, short-fill $2,100, and flash $900 out of $8,600 total, porosity and short-fill are 73 percent combined. Attack those first; the long tail of minor codes rarely justifies the engineering time.

Should scrap be tracked by shift and why?

Yes. Logging shift on every event exposes patterns a daily total hides. If night shift produces 40 percent of output but 65 percent of scrap cost, you have a training, staffing, or setup issue isolated to that crew. Shift-level data also links spikes to specific machine changeovers or operators, which speeds root cause work far more than a lumped monthly figure ever will.

What is the difference between scrap and rework cost?

Scrap is unrecoverable; the part is discarded and you lose its full accumulated cost. Rework is recoverable at the cost of extra labor and machine time to bring a part back to spec. A weld defect reworked for $6 of labor is cheaper than scrapping an $80 assembly. Track them separately, because high rework signals a fixable process while high scrap signals wasted material.

Quality and Inspection

Scrap Cost Tracker Spreadsheet Template

Log scrap events by part number, defect code, and quantity to calculate weekly and monthly scrap cost and build a Pareto of top defects.

Overview

This template gives quality engineers, line supervisors, and process technicians a running log of scrap events tied to real dollars. You record date, shift, part number, defect code, and quantity scrapped, and the sheet converts each event into cost. Scrap counted only in pieces hides the money; 40 rejected castings at $18 each is $720 that never reaches the P&L conversation. Putting a cost on every defect is what moves scrap from a shop-floor annoyance to a funded improvement target.

Each event row carries a defect code and description, quantity scrapped, and the unit cost pulled per part number. Quantity times unit cost yields scrap cost per event, and the sheet rolls those into weekly and monthly totals. A summary section groups cost by defect code so you can sort descending and read a Pareto directly. That structure means the same log that supervisors fill in daily also produces the defect ranking your root cause team needs.

Use it by logging scrap in real time at the line, one row per event, rather than reconstructing from memory at week's end. Enter each part's unit cost once so totals stay accurate. At period close, sort the defect summary to find the vital few codes driving 80 percent of cost, and divide monthly scrap cost by output value to report a scrap percentage. Pair it with the Scrap Cost Calculator to test how eliminating your top defect code changes the total.

What this template includes

Date, shift, and part number fields
Defect code and description
Quantity scrapped per event
Unit cost input for each part
Scrap cost per event calculation
Weekly and monthly scrap cost totals
Pareto-ready summary by defect code

Suggested use case

Use this to track daily scrap at a production line, prepare a monthly quality cost report, or build the defect data for a root cause analysis.

How to use it

Log each scrap event with date, part, and defect code.
Enter unit cost for each part number.
Scrap cost per event calculates automatically.
Sort by defect code at period end to build a Pareto.
Use the monthly total to report scrap cost as a percentage of output value.

Frequently Asked Questions

What unit cost should I use for scrapped parts?: Use the accumulated cost at the operation where the part failed, not just raw material. A blank scrapped before machining might carry $4 of material, but the same part scrapped after three operations may carry $22 in material, labor, and machine time. Costing scrap at its stage captures the true loss and correctly prioritizes downstream defects, which are always more expensive to throw away.
How do I calculate scrap rate as a percentage?: Divide scrapped quantity by total quantity produced over the same period. If a line runs 12,000 units and scraps 240, the scrap rate is 2.0 percent. For financial reporting, divide scrap cost by output value instead: $8,600 of scrap against $430,000 of production is 2.0 percent of output value. Track both, since a low piece rate can still be costly if the scrapped parts are high-value.
What is a good scrap rate benchmark for manufacturing?: It varies by process. Machining and assembly often target under 1 to 2 percent, while casting, molding, and stamping may accept 3 to 5 percent early in a run. World-class operations push scrap below 1 percent. Rather than chase an industry number, baseline your own line, then set a reduction goal such as cutting the current 3.2 percent to 2.0 percent within a quarter.
How do I build a Pareto chart from scrap data?: Sum scrap cost by defect code, sort descending, then compute a running cumulative percentage. Typically the top 2 or 3 codes account for about 80 percent of cost. If porosity is $4,200, short-fill $2,100, and flash $900 out of $8,600 total, porosity and short-fill are 73 percent combined. Attack those first; the long tail of minor codes rarely justifies the engineering time.
Should scrap be tracked by shift and why?: Yes. Logging shift on every event exposes patterns a daily total hides. If night shift produces 40 percent of output but 65 percent of scrap cost, you have a training, staffing, or setup issue isolated to that crew. Shift-level data also links spikes to specific machine changeovers or operators, which speeds root cause work far more than a lumped monthly figure ever will.
What is the difference between scrap and rework cost?: Scrap is unrecoverable; the part is discarded and you lose its full accumulated cost. Rework is recoverable at the cost of extra labor and machine time to bring a part back to spec. A weld defect reworked for $6 of labor is cheaper than scrapping an $80 assembly. Track them separately, because high rework signals a fixable process while high scrap signals wasted material.