Compare PCB Component Prices — LCSC vs DigiKey vs Mouser

How Three-Way Cross-Matching Actually Works

When you open the BOM panel, the viewer extracts every distinct component from your PCB — reference designators, values, footprints, and any manufacturer part numbers (MPNs) baked into the design. The first round of supplier searches uses whatever data is most specific. If the schematic carried an MPN like "Texas Instruments LM358DR," the search hits all three suppliers with that exact string and almost always returns a clean match. If only a generic value like "100nF 0603" is available, the search relies on parametric matching, which is fuzzier.

The cross-match step is where things get interesting. When LCSC returns a result with MPN "AMS1117-3.3," the viewer queues background searches for that MPN on DigiKey and Mouser, even if the original LCSC search was triggered by a different keyword. This catches the common case where a value-based search finds a part on one supplier, and the MPN field on the result is the key that unlocks accurate matches on the other two. The whole pipeline runs with an 800-millisecond rate limit per supplier, respecting their API quotas without making you wait for sequential searches.

The optimal-purchase calculation isn't a simple cheapest-price-per-line. It accounts for stock availability (out-of-stock components are excluded), price breaks at quantity tiers, and the practical reality that you usually want to consolidate to one or two suppliers per order to save on shipping. The green badge marks the cheapest in-stock supplier for each line, and the export captures that recommendation in the XLSX so your procurement workflow doesn't have to redo the math.

Reading the Pie Chart Like a Designer

The cost pie chart breaks your BOM down by component type. The first thing to notice is whether one category — usually connectors, microcontrollers, or specialty ICs — dominates the total. If a single $12 USB-C connector is half your BOM cost, you have a much higher-leverage optimization than swapping out twenty 0603 resistors. Designers using JLCPCB assembly should also note which parts are on the LCSC "Basic" library: those skip the per-part feeder-loading fee and pay back fast at small batch sizes.

Stock alerts matter most for production runs scheduled weeks out. A part that DigiKey has 50,000 of today might be on a manufacturer allocation by the time your boards are ready for assembly. The viewer shows current stock figures next to each result, but for designs you'll re-order quarterly, MakerSuite's BOM export gives you a baseline you can re-check before each batch.

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