Using Mouser’s BOM Tool for easy parts sourcing


Our parts spreadsheets are designed to simplify component sourcing. All projects from 2018 to present have been designed using standard parts available from Mouser, which ships worldwide for very reasonable costs. They also allow straightforward importing of components based on part number, so with a few clicks you can have almost a whole kit assembled for you on demand.

We’ll use the Refractor as an example since it’s our most popular project. Opening the parts spreadsheet, you’ll see two tabs after the initial instructions:

  1. The first tab, Parts List (Mouser), lists all parts that are available from Mouser, which is typically at least 90% of the components needed for the project.
  2. The second tab, Parts List (Non-Mouser), lists all of the remaining parts that need to be sourced from elsewhere, along with links to each. This always includes potentiometers and switches, but may also include other specialized parts such as NOS transistors or optocouplers.


Note: This is broken out into several steps for the sake of explanation, but it’s much easier than it looks and only takes a couple of minutes after you’ve done it the first time!

  1. Visit Mouser’s website.
  2. Click Services & Tools and then select BOM Tool. You need to be signed in for this, so if you don’t have an account then sign up for one now.
  3. On the next screen, select the Copy & Paste method. It’s significantly quicker than the spreadsheet import method.
  4. Open the Parts List (Mouser) tab of our parts list spreadsheet. Select everything in the Mouser Part # column, copy it, and paste it into the text box for Mouser’s import tool. Items appearing more than once will be automatically grouped into quantities during the import process, so all you need is the list of part numbers from the spreadsheet.
  5. Click Import My Data, then click Next.
  6. Click Process BOM. You don’t need to give the BOM a new name for future use. If you ever build the project again later, we strongly importing the BOM from scratch each time. The parts lists are periodically updated in cases of obsolescence or other availability issues.
  7. Wait for the BOM to import. It may take a minute or two depending on the number of components. Once the BOM import is finished, you’ll see a table of parts as well as current pricing.
  8. To the upper-left of the table, change Display to 100 rows. Then scroll through the list of parts looking for anything where “Availability” is zero, or the order quantity exceeds the stock. Make a note of these, then delete them using the trash icon. Most projects have fewer than 100 line items, but some of the larger ones may have a second page, so make sure you review everything.
  9. Once all the parts are reviewed, click the green Add To Cart button in the upper-right. Confirm Buy All Orderable and then click View Cart.
  10. Review the parts one more time, looking for anything that says “Backordered” that may have been missed on the previous screen. Make a note of them and remove them from the cart. Backordered parts may take several months to arrive and shipping will be charged separately, so you don’t want any of these to make it into the order.
  11. If any parts were unavailable, you’ll need to find substitutes. See Finding substitute parts below for information on how to do this.
  12. Once you’ve found substitutes for any unavailable parts, go ahead and place the order. Each line item will arrive in its own bag, clearly labeled and ready to use.

Finding substitute parts

We go through the spreadsheets a few times per year and update our parts lists, but with the global supply issues of the past few years, components go out of stock more frequently and we aren’t able to stay on top of the changes. Because of this, it’s pretty likely that you’ll encounter at least one or two parts that are unavailable, in which case you’ll have to locate substitutes on your own. We cannot help directly with substitutes, but it’s pretty simple as long as you know what to look for and what to ignore.

For passive components such as resistors and capacitors, the best way to do this is to browse to the product page for each unavailable component and use Mouser’s “Show Similar” feature. This is done by checking certain attributes of the out-of-stock component, which will then create a search for all components that match those same attributes. For our purposes, the important characteristics are the value (e.g. 10k ohms or 0.047µF), physical dimensions such as lead spacing and width, and voltage (higher voltage is always OK). The manufacturer, series, tolerance and most other attributes are not critical and should generally be left unchecked.

For active components with standardized names, e.g. 1N5817 or LT1054, it’s recommended just use the main search instead and see what comes up, since these parts are usually available from more than one manufacturer. Make sure to filter by through-hole components only, since most ICs also come in surface-mount variants that have the same name with a different suffix.

Other notes

The parts spreadsheets are provided as a convenience only. When parts are out of stock, we periodically switch them out with equivalents based on reviewing specifications. However, we have not always tested each exact part number in each project. On occasion we may misread something or the specifications may be inaccurate. Please let us know if anything is in error.

If you want to edit a parts spreadsheet, you can do so by selecting File → Download to download as an .xlsx Excel file, which can then either be edited locally or uploaded to your own Google Docs account. Please do not request access to the parts spreadsheets as we are unable to share them.