PCBA Array Panel Yield and Cost Per Good Board Calculator
How boards are arrayed and whether X-outs are accepted can move cost per good board by more than a component price negotiation. This calculator lays out the array, computes utilization, and shows the yield math behind the cost.
Your numbers
Largest width your line and fixtures handle, including tooling rails.
Length along the conveyor direction.
Rails run on the two sides that touch the conveyor.
Routing channel or V-score allowance between adjacent boards.
Cost of one bare array from the fabricator.
Print, place, reflow and inspect, per array.
Probability that an individual bare board is good.
Probability a good bare board survives assembly without scrap.
Your results
Simplified independent-yield model: board yields are assumed independent and identical. Real defects cluster by lot and panel position. Check your IPC-6012 or customer acceptance terms for X-out rules.
Cost per good board vs bare board yield
Sweeps Bare board yield per board from 90 to 100, holding your other inputs fixed.
Link yield history to your quotes
An optional review of how scrap and yield data in your ERP could drive quoting assumptions.
Optional. The tool and every export work without this. No spam.
How to use it
Enter finished board dimensions, the largest array your line can run, the rail width, and the routing or V-score gap. Then enter bare array cost, component cost per board, assembly cost per array and the per-board yields. Choose whether your customer or process allows X-out boards, meaning bad boards that are marked and skipped. The calculator tells you how many boards fit, how efficiently the array uses its area, and what each good board really costs.
The yield model
With independent board yields y, the probability that all n boards on an array are good is y to the power n. If X-outs are not allowed, an array is only good when every bare board is good, so expected good boards are n times assembly yield times y to the n. If X-outs are allowed, good boards are n times y times assembly yield, and components are not placed on marked bad boards, which also trims cost. This is the standard series-system yield calculation.
- P(array fully good) = y^n
- Good boards, no X-out = n x a x y^n
- Good boards, X-out = n x y x a
- Cost per good = array cost / good boards
Reading the result
A large array at 97.5 percent bare yield has under a 50 percent chance of being fully good once n reaches about 28, so a no-X-out rule can make big arrays expensive. Use the sweep to see how sensitive cost is to fabricator yield, then decide between a smaller array, an X-out agreement with the customer, or a better fabricator. Utilization highlights wasted laminate in the bare board price, which you may want to renegotiate or lay out differently.
Common mistakes
People often assume X-outs are free to accept. They require the customer to agree, a clear marking method, and pick-and-place programs that can skip marked boards through bad mark recognition. Another mistake is ignoring the rail width and fiducial keep-outs when fitting boards. Do not treat yield as independent when a fabricator problem hits one lot: the real distribution has fatter tails. Always confirm panel limits with your line before quoting a layout.
- Confirm X-out acceptance in writing
- Reserve rails, fiducials and tooling holes
- Check depaneling method fits the gap
- Use lot data, not only averages, for yield
Frequently Asked Questions
What is an X-out board?
An X-out is a bare board in an array that failed fabrication test and is marked, often with an X or a bad board mark, so assembly skips it. Acceptance limits are agreed between customer and fabricator and should be defined in the purchase terms.
Does a bigger array always lower cost?
Not always. Bigger arrays reduce handling per board but increase the chance that an array contains a bad board and strain warpage and line limits. The best size comes from the yield and cost trade-off shown here.
Which yield should I use for fab yield?
Use the per-board acceptance rate from your fabricator's lot data, or your incoming inspection history. If you only have per-panel yield, convert it to a per-board figure using the number of boards per fabrication panel.
Why is the assembly yield separate?
Bare board defects and assembly defects have different causes and different costs. Separating them shows where improvement pays off, and lets you keep component cost from being wasted on boards that were bad before assembly.
If you track array yield and scrap by lot, we can connect that data to your quoting and planning in ERP so assumptions are based on history, not guesses.
Related Tools
SMT Placement Cost Per Board Calculator
Convert placement counts and rated CPH into realistic cycle time, boards per hour and placement cost per board and per placement, including job setup.
Costing & FinancePCBA NRE and Stencil Amortization Per Unit Calculator
Amortize stencil, programming, fixture and DFM NRE plus line setup and first article time over your order size, then see loaded cost, quoted unit price and how much of the price is one-time cost.
Costing & FinancePCBA Turnkey Quote Worksheet with BOM Rollup and Attrition
Enter BOM lines with quantity per board, unit price, attrition and placement counts, then roll up material, placement and through-hole cost into a per-board cost and quote price.
Quality & InspectionPCBA Quote Data Package Completeness Checklist
A checklist of the design, BOM, assembly, test, commercial and compliance data an EMS provider needs before it can quote a PCBA without padding for unknowns.
More Quality & Inspection tools
See all- PCBA AOI Defect Log and DPMO Worksheet
- PCBA RMA Failure Analysis Report Template
- SMT First Pass Yield and Rolled Throughput Yield Calculator
- Incoming Electronic Component Inspection Record Template
- ESD Protected Area Audit Checklist (ANSI/ESD S20.20 Style)
- PCBA Test Strategy Cost Per Board Calculator (ICT vs Flying Probe vs Functional)
- SAP QM Process Capability Cp Cpk Calculator
- SAP QM Lot Rejection Rate, PPM and Sigma Level Calculator
- SAP QM Gauge R&R Study Calculator
Keep exploring
Free tools
- PCB Panel Utilization and Boards per Panel CalculatorSee how many boards fit on a fabrication panel after rails and spacing, with utilization and cost per board.
- PCBA Rework Cost Tracking WorksheetLog rework events by work order, defect type, time and material, and get rework cost per line and per board.
- Furniture Cut List and Panel Yield WorksheetAn editable cut list that totals part area and estimates how many board sheets a furniture job needs, exportable to Excel.
Guides
- PCBA Quoting Software for EMS CompaniesHow EMS and PCBA shops evaluate quoting software: BOM import, live distributor pricing, assembly labor models, NRE, and how quotes tie back to the ERP.
- ERP for Contract Electronics ManufacturersWhat an ERP needs for EMS and PCBA shops: multi-level BOMs, AML, lot and reel traceability, kitting, ECN control, and how common systems fit the job.
- IPC-A-610 Class 2 vs Class 3: How It Affects Your PCBA QuoteHow the IPC class requirement changes PCBA cost and risk: inspection time, rework limits, training, documentation, and how EMS shops should price Class 3.