Engineering utilities / 03 in the stack

Every revision
accounted for.

Two versions of your bill of materials. One precise change report. Catch additions, quantity shifts, part revisions, spec edits and cost movement before a release.

Excel · CSV · TSVNo signupRuns on your device

01 — SOURCE FILES

Load two revisions

Use flat BOM exports with a header row. Matching is based on part numbers, not row order.

Previous revision

Approved baseline / earlier export

BEFORE

Choose or drop your previous BOMXLSX, CSV or TSV · up to 5 MB

No file selected

Updated revision

Proposed release / most recent export

AFTER

Choose or drop your updated BOMXLSX, CSV or TSV · up to 5 MB

No file selected

Data is processed in this tab and is not uploaded or autosaved.

02 — FIELD ALIGNMENT

Match your columns

Confirm what each source column means. Only fields present on both sides are compared.

Waiting for files

A Previous columns

B Updated columns

Combine repeated part numbers Only if description, revision, unit, manufacturer and cost match within each file. Ignore letter case in part numbers Off by default. Leading and trailing spaces are always trimmed.

Review before approving a changeThis reports differences in the uploaded flat BOMs. It cannot certify interchangeable parts, assembly hierarchy, approved substitutes or manufacturing readiness.

03 — REVIEW & EXPORT

Change register NOT RUN

Your parts, quantities and field-level changes appear here after comparison.

Changed parts—Modified existing items

Added / removed—New and discontinued lines

Quantity shifts—Parts with quantity changes

Extended cost movement—Both files need unit costs

≡

The change story starts here.

Import or try the included pair of BOMs, check the mapped columns, and run a comparison. You’ll get an inspectable change register and CSV report.

A responsible comparison

Clear differences.
No invented certainty.

Compare like with like

Use exports from the same assembly and variant. Record the actual approved baseline and proposed revision; filenames alone do not establish release status.

Quantities are literal

The tool compares supplied quantities as entered; it does not normalize units, expand nested subassemblies, interpret alternate parts or convert per-board quantities into production orders.

Cost is a supplied estimate

Extended cost is quantity × the entered unit cost, rounded to cents per part. It is not a live quote or purchasing forecast; mixed currencies and pack bases must be resolved before use.

Tool reference

Common questions

What BOM formats are supported?

Standard Excel .xlsx workbooks and UTF-8 comma-, semicolon- or tab-delimited CSV/TSV/text files. For Excel, choose a worksheet and its header row (1–50). Up to 5 MB per file, 10,000 data rows and 80 columns. Formatted part IDs retain leading zeros; numeric quantity/cost cells use their stored values. Formulas use saved results and are never calculated here. Recalculate and save in Excel first. Merged table cells, Excel errors, encrypted files, .xls/.xlsm, PDF, CAD files and nested assemblies are not supported.

What happens with duplicate part numbers?

The comparison rejects duplicates by default, with source row numbers. Optional aggregation adds quantities only when the duplicate lines agree on their mapped revision, description, unit, manufacturer and cost. No mismatched rows are merged.

How are costs compared?

If cost columns exist on both sides, unit costs and extended cost changes can be compared. Missing costs prevent the full total estimate. Part numbers and decimal values are treated as text and precise decimal quantities, respectively; currency conversion is not attempted.

Can this approve an engineering change?

No. The report identifies differences within the uploaded tables. A responsible ECO review still verifies drawing revisions, component equivalence, configuration, regulatory requirements, routing and release approval.