What Is an MPN? How to Find and Use Manufacturer Part Numbers

A manufacturer part number (MPN) is a unique alphanumeric code a manufacturer assigns to identify a specific product or component.

To find, use, or manage MPNs effectively, you'll need to know how they're structured, where to locate them, and how they differ from SKUs, UPCs, and serial numbers.

Here's the step-by-step process.

What is a manufacturer part number (MPN)?

A Manufacturer Part Number (MPN) is an exclusive alphanumeric code given by the original manufacturer to identify a specific product or component. You can typically spot these identifiers on the product label or even etched directly onto the item itself.

Think of the MPN as a unique fingerprint that sets a particular item apart from everything else in a manufacturer's product line. No two products from the same manufacturer share the same MPN, which makes it the most reliable way to ensure you're ordering, stocking, or replacing the exact right part.

The format and length of an MPN can vary depending on the manufacturer. It could be a series of letters, numbers, or a blend of both. Sometimes, it may contain additional information like version numbers, revisions, or product variants. For example, a resistor from one electronics manufacturer might carry an MPN like RC0805FR-0710KL, where segments of the code indicate size, tolerance, and resistance value.

Manufacturer part numbers are widely used across industries, including:

• Manufacturing
• Electronics
• Automotive
• Aerospace
• Appliances
• Power tools
• Plumbing
• Medical devices
• Pharmaceuticals

MPNs help suppliers, distributors, and customers communicate and coordinate effectively when searching for, ordering, or replacing parts.

What does MPN mean?

MPN stands for Manufacturer Part Number. It's the code that the original manufacturer assigns to a product — not the retailer, not the distributor, and not the warehouse. This distinction matters because the same physical product might carry different SKUs at different retailers, but the MPN stays the same regardless of where it's sold.

You'll sometimes see variations like "manufacturer number," "manufacturing part number," or "MPN number" used interchangeably. They all refer to the same thing: the identifier that traces back to the company that made the product.

How to find a manufacturer part number

Most products will have an MPN inscribed directly on them. The exact location can vary significantly depending on the product. A careful examination of your product should uncover this code, typically on the underside, backside, or nameplate of the item.

In some instances, the MPN might not be engraved on the product itself. Instead, it may be documented in the instruction manual or supplementary information notes accompanying the product.

Step-by-step guide to finding an MPN

Check the product packaging. The MPN is often printed on the box, along with other product details like the barcode and model number.

Look in the user manual. The MPN is typically listed in the product specifications or details section.

Inspect the product itself. The MPN is often printed, engraved, or etched onto the product — especially on electronic, mechanical, or automotive components.

Search the manufacturer's website. Enter the product name or model number on the manufacturer's site. The MPN is usually listed in the product description or specifications page.

Use an MPN lookup tool. Several third-party databases (like Octopart for electronics) let you search by product description or cross-reference number to find the correct MPN.

Contact the manufacturer or retailer. If none of the above methods work, reach out directly. Provide as much identifying information as you can — model name, product description, photos — and they can help you locate the MPN.

Note: The location of the MPN can vary greatly depending on the product and manufacturer. On a circuit board, it might be silk-screened next to the component. On an automotive part, it could be stamped into the metal housing.

MPN examples by industry

It helps to see what manufacturer part numbers actually look like in practice. Here are examples across common industries:

Notice that each MPN format is different. There's no universal standard for how MPNs are structured — each manufacturer creates their own system. What matters is that the code is unique within that manufacturer's catalog.

Why are MPNs important?

The manufacturer part number plays a crucial role in ensuring accurate and efficient product identification. It helps avoid confusion between similar products, ensures compatibility when ordering replacement parts, and makes it easier to track a product's lifecycle.

Here are the major reasons MPNs matter for your business:

Accurate product identification

In a catalog with thousands of similar-looking components, the MPN is the one identifier that points to the exact item you need. This eliminates mix-ups that can cause production delays or quality issues. For example, two capacitors might look identical but have different voltage ratings — the MPN tells you exactly which one you're dealing with.

Better inventory management

MPNs give each product a consistent identifier that doesn't change across locations or systems. This simplifies monitoring stock levels, makes reordering more accurate, and helps you avoid both stockouts and overstock situations. When your inventory management system uses MPNs, you can track exactly what you have — down to the specific revision or variant.

Supply chain coordination

Think of the MPN as a universal language across your supply chain. When everyone — suppliers, distributors, logistics providers — references the same MPN, communication becomes much cleaner. Orders are placed correctly the first time. Receiving teams can verify shipments against purchase orders. And returns or replacements happen faster because there's no ambiguity about which part is involved.

Product alternatives and substitutions

When a part is discontinued or out of stock, the MPN gives you a starting point for finding compatible replacements. Many electronic component distributors, for instance, maintain cross-reference databases where you can enter an MPN and find equivalent parts from other manufacturers.

Warranty and service support

When you file a warranty claim or request a repair, the MPN tells the service provider exactly which product you have. This speeds up the process and ensures you receive the correct replacement part — not something that looks similar but doesn't fit.

Cross-referencing and compatibility

In industries like electronics and automotive, components from different manufacturers must work together. MPNs make it possible to verify compatibility, cross-reference parts from multiple sources, and ensure that substitutions won't cause failures. This is especially critical when managing a complex bill of materials with hundreds of components.

How are MPNs used in practice?

Manufacturer Part Numbers show up throughout the product lifecycle. Here's how businesses use them day to day:

Procurement — Buyers include the MPN on purchase orders to ensure they receive the exact right product from suppliers. No ambiguity, no wrong shipments.

Inventory tracking — MPNs let you monitor stock levels, track inventory movements, and maintain accurate counts. You always know what's on the shelf and what needs reordering. Combined with lot numbers, MPNs give you both product-level and batch-level visibility.

Product catalogs and databases — MPNs provide the backbone of product catalogs, linking to specifications, descriptions, and pricing. This makes it straightforward for customers and suppliers to find the right product.

Cross-referencing and substitution — Can't find the original part? MPNs make it easy to cross-reference products from different manufacturers and find compatible alternatives.

Warranty and service support — By providing the MPN, you help the service provider identify the exact product, which speeds up repair, replacement, or technical support.

Product research and comparison — Engineers and purchasing teams use MPNs to compare specifications across manufacturers and select the right component for their application.

Supply chain traceability — MPNs facilitate tracking products from the manufacturing line to the customer's doorstep. For industries with recall requirements, this traceability isn't optional — it's essential.

Note: While MPNs are widely used, not all manufacturers assign them, and some don't use them consistently across all their products. In these cases, you may need to rely on model numbers or internal part codes.

How MPNs are used across industries

Automotive — Tracking parts from dozens of manufacturers is a massive challenge. MPNs keep a clear inventory of components and ensure the correct parts are used during repairs and assembly.

Electronics — Thousands of different components go into electronic devices, from resistors to microchips. Without MPNs, identifying the correct part for repairs or production would be nearly impossible. Many electronics manufacturers rely on MPN databases to source components globally.

Aerospace — Safety is non-negotiable. MPNs provide a reliable system of part identification that minimizes the risk of human error during aircraft manufacture, maintenance, and repairs.

Retail — Retailers use MPNs alongside SKUs to manage vast amounts of stock and ensure accurate order fulfillment.

Pharmaceuticals — MPNs help differentiate between similarly named drugs and track batches for quality control and recall purposes.

Is an MPN the same as a SKU?

No. An MPN and a SKU serve different purposes, and they come from different sources.

The MPN is assigned by the manufacturer and stays the same no matter where the product is sold. It identifies the product at the source.

A SKU (Stock Keeping Unit) is assigned by the retailer or distributor for their own internal tracking. The same product might have completely different SKUs at different stores. For example, a drill bit with MPN DW1361 from DeWalt would carry different SKUs at Home Depot, Amazon, and a local hardware distributor.

Here's a quick comparison:

If you're building SKU numbers for your own inventory, you might incorporate the MPN as part of your SKU structure for easy cross-referencing.

What are the alternatives to MPNs?

MPNs aren't the only product identification system out there. Here are the most common alternatives and how they compare:

Universal Product Codes (UPCs)

A Universal Product Code (UPC) is a 12-digit number represented by a barcode, primarily used in retail for scanning at the point of sale. Unlike an MPN, a UPC is tied to a product listing and registered through GS1.

European Article Numbers (EANs)

The European Article Number (EAN) is a barcode-based system used internationally. It's similar to the UPC but typically contains 13 or 8 digits. You'll see EANs on products sold in Europe, Japan, and other regions.

Stock Keeping Units (SKUs)

Stock Keeping Units (SKUs) are alphanumeric codes created by retailers to track products within their own inventory system. They are often used alongside UPCs or MPNs but are fully customizable by the business that creates them.

Serial numbers

Serial numbers are unique identifiers assigned to individual units during manufacturing. While an MPN identifies a product type, a serial number identifies a specific unit of that product. Serial numbers are essential for warranties, service tracking, and recalls in industries like electronics, appliances, and automotive.

Industry-specific codes

Certain industries use their own coding systems. The defense industry uses National Stock Numbers (NSNs) for military equipment. The healthcare industry uses Unique Device Identifiers (UDIs) for medical devices. These systems address regulatory and traceability requirements specific to those sectors.

Custom part numbers

Manufacturers or suppliers sometimes create internal part numbers that don't follow any industry standard. These work fine within a single company but can cause confusion when communicating with external partners. If you're building a part numbering system, it's worth referencing the MPN alongside your custom code.

The choice of identification system depends on your industry, supply chain requirements, and how you need to communicate with trading partners. In most manufacturing contexts, MPNs remain the most widely recognized standard.

How to use MPNs in Google Shopping and ecommerce

If you sell products online, MPNs play a direct role in how your products appear in search results. Google Merchant Center uses the MPN attribute (along with brand and GTIN) to identify and match products. Submitting accurate MPNs can improve your product listings' visibility and reduce disapprovals.

Here's what you need to know:

Google requires either a GTIN or MPN + brand for most product categories. If your product doesn't have a GTIN (Global Trade Item Number), the MPN becomes essential.

Accurate MPNs improve product matching. Google uses MPNs to group identical products from different sellers, which can increase your listing's exposure.

Incorrect MPNs can hurt you. If you submit the wrong MPN, your product may be matched to the wrong listing or flagged for data quality issues.

For growing manufacturers who sell direct-to-consumer or through online channels, getting your MPN data right in your product feeds is a simple step that can measurably improve your ecommerce performance.

Frequently asked questions

What is your product's manufacturer part number (MPN)?

Your product's MPN is the unique alphanumeric code assigned by the original manufacturer. It identifies that specific product or component within the manufacturer's catalog. You can find it on the product label, packaging, user manual, or the manufacturer's website.

How do you find a manufacturer part number?

Check the product packaging first, then the user manual, then the product itself (labels, engravings, or nameplates). If you still can't locate it, search the manufacturer's website by model name or contact the manufacturer directly.

Is an MPN the same as a SKU?

No. An MPN is assigned by the manufacturer and stays consistent everywhere the product is sold. A SKU is created by the retailer or distributor for internal inventory tracking. The same product can have different SKUs at different sellers but only one MPN.

Is an MPN the same as a part number?

It depends on context. An MPN is specifically the part number assigned by the original manufacturer. Other entities in the supply chain — distributors, retailers, or your own warehouse — may assign their own part numbers to the same product. When someone says "part number" without qualification, they could mean any of these. When accuracy matters, always reference the MPN.

Track MPNs and every part in your inventory with Brahmin Solutions

When you’re managing hundreds of components, keeping MPNs, internal SKUs, and supplier part numbers aligned is critical — one mismatch means ordering the wrong resistor or stocking a discontinued connector. In Brahmin, every item carries its MPN alongside your internal SKU, so purchasing, receiving, and production all reference the same part unambiguously.

MPNs tie directly into your bills of materials, which means when you explode a BOM for a production run, the system knows exactly which manufacturer part goes into each assembly — and whether you have enough on hand or need to reorder from the right supplier. If you’re tracking parts across multiple suppliers and need your MPNs, SKUs, and BOMs to stay in sync, book a demo and see how it works with your parts catalog.