Convert BOM PDF to Excel on Mac: Bill of Materials by Part

To convert a BOM PDF to Excel on a Mac, use a tool that reads the parts table and returns one row per line: level, item number, part number, description, quantity, unit, reference designators, manufacturer and manufacturer part number. Keep an indented BOM’s structure as a level column and each line’s designators in one cell, then check that the item numbers run without gaps and that quantities match the designator counts before the sheet goes to purchasing or a distributor’s BOM tool. If you can get the BOM from the CAD or PLM system that produced it, export that instead.

The Mac app for the PDF case is ignitai. It reads each page with Apple’s on-device text recognition, and an AI builds the table your plain-English instruction describes, so one instruction covers a PLM report, a customer’s RFQ package and the parts list on a scanned assembly drawing. The page images stay on your Mac; only the recognized text goes to ignitai’s servers, where the spreadsheet is built.

The BOM arrives as a PDF more often than anyone would like. A contract manufacturer gets a customer’s quote package with the bill of materials as a PDF report. A maintenance team has a machine’s spare parts list only in the manual. A legacy product survives as released drawings, with the parts list on the assembly sheet and no CAD file anyone can open. Purchasing needs every one of them as rows: to quote, to kit, to order.

In this guide11 sections

Why BOMs break PDF-to-Excel converters

1. Descriptions wrap. “RES, 10K, 1%, 0603, 1/10W, THICK FILM” runs onto a second line, and a grid-based converter turns the second line into a row of its own with no part number.
2. Designator lists run long. “C1, C4-C9, C12, C15, C21-C24” wraps across three lines, and it’s the field that has to agree with the quantity.
3. Structure lives in indentation. A multi-level BOM shows parent and child by indenting the part number, or with level marks such as 1, .2 and ..3. Indentation is the first thing a table extractor throws away, and without it a subassembly’s parts look like top-level parts.
4. Drawing parts lists read upward. On an assembly drawing, the parts list often sits on top of the title block with the column headings at the bottom and item 1 just above them, so the list reads from the bottom up. The same sheet is full of other text: dimensions, notes, a revision block.
5. Remarks hide in the lines. “DNP” (do not populate), “Not shown”, “Ref only” and approved alternates printed under the main part number all change what gets bought.

Convert a BOM PDF to Excel on Mac with ignitai

1. Gather the PDFs. A BOM report, an assembly drawing with a parts list, or a scanned manual page all work, and born-digital and scanned PDFs can go in the same batch. Photos of a printed BOM run as a batch of their own, because on Mac a drop that mixes PDFs and image files imports only the PDFs.

2. Drag the PDFs onto the ignitai window, open them with ⌘O, or right-click them in Finder and choose Open With. A printed BOM on the bench can come in through File ▸ Import from iPhone or iPad, which scans it with your iPhone’s camera.

3. Describe the rows. A prompt is required, so the Convert button stays disabled until you type one:

   “One row per BOM line. Columns: assembly_number (the top-level part number printed in the header or title block, repeated on every row), level (a whole number: 1 for items directly under the top assembly; count indent steps or dots for deeper levels), item_number, part_number, revision, description (the full text, joined if it wraps), quantity, unit (EA if not printed), reference_designators (exactly as printed, in one cell, ranges such as C4-C9 kept as written), manufacturer, manufacturer_part_number, alternate_mpn (an approved alternate printed for the line), notes (DNP, reference only or other remarks). Skip page headers, title blocks, revision blocks and drawing notes. Quantities as plain numbers.”

   For an assembly drawing, add: “Read only the parts list table above the title block.” Save the instruction, and the next BOM is one click away.

4. Check the page count, then Convert. Before the run starts, ignitai shows how many pages it will use and how many you have left. Each file shows its status as it runs, and a notification arrives when the spreadsheet is ready.

5. Check the table in ignitai. Rows are numbered, so on a single-level BOM the last row number should match the last item number. Original Pages keeps every BOM page a click away. If a column came back empty, ignitai says so: an empty reference_designators column is normal for a mechanical BOM and wrong for a circuit board.

6. Export to Excel. Quantities are real numbers in the Excel file, so they total the moment it opens; the header is bold and the columns fit their content. Corrections happen in Excel or Numbers.

There is no filename column. Filenames never leave your Mac, so a batch of several assemblies can’t say which file a row came from. That’s why the instruction repeats assembly_number on every row; it’s printed on the BOM. If one prints it only on the first page and later rows come back without it, convert that BOM on its own.

Big products and the page allowance. Most BOMs run a few pages. A full product’s drawing package can run to hundreds, so convert only the parts-list pages rather than every sheet. The plan includes 80 pages a week, up to 320 a month, and unused weekly pages don’t carry over; ignitai shows the page count before converting, and extra pages cover the rest. Prove the instruction on one BOM of four pages or fewer first.

Get ignitai on the App Store — free download; your first document (up to 4 pages) converts free with Sign in with Apple, and one subscription covers iPhone, iPad, Mac, and Vision Pro.

Indented BOMs: rebuild the structure in Excel

With the instruction above, the columns run assembly_number (A), level (B), item_number (C), part_number (D), revision (E), description (F), quantity (G), unit (H), reference_designators (I) and on to notes (M). Keep the rows in the order the BOM prints them, parents above their children, and two helper columns turn the level numbers back into a tree:

1. Parent part number. In column N, =XLOOKUP(B2-1,B$1:B1,D$1:D1,"top",0,-1) searches upward from each row for the nearest row with a level one lower and returns its part number. The last argument, -1, makes XLOOKUP search from the bottom of the range, which is what “nearest row above” means. Level 1 rows have no parent and show “top”.
2. Extended quantity. In column O, =G2*XLOOKUP(B2-1,B$1:B1,O$1:O1,1,0,-1) multiplies each line’s quantity by its parent’s extended quantity, so a screw used four times in a bracket that appears twice reads 8. XLOOKUP needs Excel 2021 or Microsoft 365.
3. Roll up the buy list. A PivotTable with part_number as rows and the sum of extended quantity as values gives the total per part for one assembly. Filter out the subassemblies you build in-house, since you buy their parts, not them.

Parent and child as separate columns is also the shape most MRP and ERP systems expect when they import a BOM from CSV: one row per component with its parent and quantity per parent.

Check the extraction before anyone orders

• Item sequence. Item numbers usually run 1 to N. On a single-level BOM, sort a copy of the sheet by item_number and add =C3-C2 beside it; any value other than 1 is a gap or a duplicate to look up in Original Pages. Skipped item numbers do exist on real BOMs, so confirm before you add a row.
• Designators against quantity. For comma-separated designators, =LEN(I2)-LEN(SUBSTITUTE(I2,",",""))+1 counts the entries. Ranges such as C4-C9 count as one entry there, so check the rows with a hyphen by eye. A count that doesn’t match quantity is a misread or a mistake in the BOM itself, and both need an answer before a kit is pulled.
• Look-alike characters. O and 0, I and 1, S and 5, B and 8. A misread manufacturer part number orders the wrong part. Distributor BOM tools flag part numbers with no match, which makes the upload a useful check in itself.
• Leading zeros. A part number made only of digits, such as 0012345, can lose its zeros on the way into a spreadsheet. Compare a few against Original Pages; if they’re short, rebuild the column as text with =TEXT(D2,"0000000") at your numbering scheme’s length.
• DNP lines. Filter notes for DNP and reference-only lines, and keep them out of the buy quantities.
• Totals. Where the BOM prints a total part count or placement count, add up the quantities in Excel and compare.

From the sheet to quotes, orders and distributor tools

• Distributor BOM tools. Mouser’s BOM Tool takes an XLS, XLSX or CSV file under 4 MB and remembers your column mapping for the next upload; Digi-Key, Arrow and Octopart offer comparable upload tools. Map manufacturer_part_number and the quantity (extended quantity times your build quantity, plus attrition for small parts) and the tool prices the build and shows stock.
• Requests for quotation. Send the cleaned sheet as your RFQ, and the answers come back as quotes; the quote guide lines up the suppliers’ replies by item.
• Purchase orders and receiving. Once orders go out, the purchase-order workflow turns the PO PDFs into lines to match against the BOM, and the packing-list guide does the same for what arrives.
• Supplier catalogs. Standing prices for the parts usually come as a catalog rather than a quote; the price-list guide covers that document.

A bill of materials is not a bill of quantities. The construction document of a similar name measures work items with rates; the BOQ guide covers that one.

Other ways to get a BOM into Excel

• Export from the source. SolidWorks, Inventor, Fusion, Altium, KiCad and most other CAD and EDA tools export a BOM straight to Excel or CSV, and PLM systems export their BOM reports the same way. If the design owner or customer can send the native export, ask for it. Nothing beats data that never became a PDF.
• Copy and paste from Preview. A short, born-digital BOM with one line per part pastes reasonably well. Wrapped descriptions and designator lists split into extra lines, which is the cleanup you were trying to avoid.
• Acrobat’s Export PDF to Excel. It keeps the page geometry, so the wraps become extra rows and the indentation becomes leading spaces or nothing at all.
• Excel for Mac’s Get Data. Power Query is under Data ▸ Get Data, but Excel for Mac has no From PDF connector; that one is Excel for Windows only.

On iPhone and iPad

• iPhone. The spare parts list in a machine manual on the shop floor: scan the page with the camera in ignitai, tap the saved instruction, and follow progress on the Lock Screen and in the Dynamic Island.
• iPad. BOM PDFs that arrive by email can be multi-selected in the Files picker or sent from Mail through the share sheet (there’s no external drag-and-drop into the app on iPad). Sort the finished table by part number, then select rows and copy them before you export.

One subscription covers iPhone, iPad, Mac and Vision Pro, and finished files open on your other devices after Sign in with Apple.

Design data and confidentiality

A BOM shows how a product is built and who supplies it. In this workflow the page images stay on your Mac. The recognized text of every page goes to ignitai’s servers, where the AI builds the sheet, and that includes fields you leave out of the instruction. The finished file is stored in your ignitai account until you delete it, and any file, or the whole account, can be deleted from inside the app. If the BOM came under an NDA or is export-controlled technical data, check the rules that apply before converting.

When not to use this

• The native BOM exists. Export it from the CAD, EDA, PLM or ERP system.
• Five lines. Type them.
• Handwritten redlines. Markups and hand-corrected quantities are outside what this guide covers; it’s for printed and typed BOMs.
• An unreadable scan. A parts list scanned from a large-format print at low resolution: if you can’t read it zoomed in, rescan it at a higher resolution first.

Bottom line

To convert a BOM PDF to Excel on a Mac, drag the BOM or the drawing’s parts-list pages into ignitai and ask for one row per line with the assembly number repeated on each row, a whole-number level, the part number, description, quantity, designators and manufacturer part number. In Excel, XLOOKUP rebuilds each part’s parent and extended quantity, and a PivotTable rolls up the buy list. Check the item sequence, the designator counts and the look-alike characters in part numbers before the sheet reaches a distributor’s BOM tool or a purchase order. When the CAD or PLM export exists, use it instead.

FAQ

How do I convert a BOM PDF to Excel?

On a Mac, drag the BOM PDF into ignitai and ask for one row per line with the level, item number, part number, description, quantity, unit, reference designators, manufacturer and manufacturer part number. Convert to Excel, then check that the item numbers have no gaps and that each line’s quantity matches its designators before anyone orders from it.

Can I extract the parts list from an assembly drawing PDF?

Yes, when the parts list is printed or typed on the sheet. Tell the instruction to read only the parts list table and to skip dimensions, notes, the title block and the revision block. Drawing parts lists often number upward from the title block, so sort by item number after export.

How do I keep the levels of an indented BOM in Excel?

Ask for a level column as a whole number, with 1 for parts directly under the top assembly. In Excel, an XLOOKUP that searches upward from each row finds its parent, the nearest row above with a level one lower, and multiplying quantities down that chain gives each part’s extended quantity.