FREE TOOLS Compare Two BOM CSV Files Match part numbers and review quantity, description and material changes between two flat BOMs.
● Runs on your device; privately savedInputs, files and results retained. Run and save with MST Running a tool sends the inputs, selected original files and results to MST’s private storage. MST administrators can review them. Files stay until you or an administrator delete them and are not used for model training. Analysis for this tool runs on your device; saved results are marked as browser-reported. Up to 32 attachments, 25 MB each, 100 MB total; input and result text up to 2 MB.
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Part numbers are case-sensitive. Duplicate part numbers must be resolved first. Compare BOMs →
SYNTHETIC WORKED EXAMPLE What changed in this bracket assembly’s parts list? Quick sample: two flat BOM revisions, four rows each. The complete drawing-to-BOM lab uses its own five-row files. These are the expected findings from the sample, not results from your files.
Load both revisions. Choose Try sample revisions above, or download the two CSVs and open them with Choose CSV.Check the column mapping. Confirm part number, quantity, description and material. Select Compare BOMs.Review and export. Expect 1 added, 1 removed, 2 changed and 1 unchanged part. Export the full comparison as CSV.How to compare two BOM CSV files by part number Export each BOM as CSV UTF-8 from your spreadsheet or CAD/PDM system. Map the part number and quantity columns, then compare. Description and material changes appear when those columns are included.
Rows match by the exact, trimmed part number. A changed part number appears as a removal and an addition. Item order is ignored. Quantities must use decimal numbers with a dot, without units or thousands separators; this tool does not convert units or reconcile assembly hierarchies.
Follow the BOM revision comparison exercise → BOM still in a drawing? Extract the table first → Review repeated parts and missing quantities → Preparing P&ID, BOM and model data for an assembly workflow →