What Is a SKU Code?
A SKU — Stock Keeping Unit — is a unique alphanumeric code that identifies a specific product in your inventory. Think of it as a product's internal ID: it tells you exactly what something is, where it fits in your catalogue, and how to track it across warehouses, sales channels, and accounting systems.
SKUs are not standardised across businesses — unlike barcodes (EAN/UPC) or ISBNs, you create your own SKU system. This flexibility lets you design codes that carry real meaning about the product: its category, variant, colour, size, or supplier. A well-designed SKU system is the backbone of efficient inventory management.
A typical SKU might look like:SHIRTS-BLU-M-0042
→ Category: Shirts | Colour: Blue | Size: Medium | Item #42
Why Every Business Needs a SKU System
Whether you sell on Amazon, Shopify, a local market, or a wholesale catalogue, SKUs are essential once your product count grows beyond a handful of items. Here's why:
Inventory Accuracy
Without SKUs, inventory tracking is done by product name — and names are ambiguous. "Blue T-Shirt" could be three different products. SKUs eliminate confusion by giving every variant a unique identity.
Faster Order Fulfilment
Warehouse staff and dispatch teams use SKUs to pick, pack, and ship orders faster. Scanning a SKU is quicker and more reliable than reading a product description.
Multi-Channel Selling
If you sell on Amazon, Flipkart, your own website, and wholesale — SKUs let you map the same product across all channels. When one channel sells out, your system updates everywhere.
Reduced Errors
Returns, exchanges, and purchase orders all rely on accurate product identification. A SKU system reduces mis-picks, wrong shipments, and restocking errors significantly.
Better Reporting & Analytics
Sales reports, slow-moving stock analysis, and reorder alerts all depend on product-level tracking — which requires unique identifiers. SKUs make reporting possible at the variant level.
Supplier & Purchase Order Management
When placing orders with suppliers, referencing SKUs avoids confusion about which specific variant (size, colour, pack size) you're ordering. Use our Purchase Order Generator to list SKUs on supplier orders.
How to Generate SKU Codes — Step by Step
This tool generates ready-to-use SKU codes in seconds. Here's how to use it:
Step 1 — Enter a Prefix
The prefix is a short code that represents your brand, product line, or store. It goes at the beginning of every SKU.
Example: TG for Tools Galaxio, NIKE for a Nike product line, SS25 for a Spring/Summer 2025 collection.
Step 2 — Enter a Category Code
The category code identifies the product type or department.
Example: SHIRTS, ELEC, BOOK, FURN, SHOE
Keep it short — 3 to 6 characters is ideal.
Step 3 — Choose a Separator
The separator is the character between each segment of the SKU. Common options:
- Hyphen (
-) — most common, e.g.TG-SHIRTS-001 - Underscore (
_) — e.g.TG_SHIRTS_001 - None — e.g.
TGSHIRTS001
Hyphens are the industry standard and work across all platforms.
Step 4 — Set the Starting Number
Choose where your SKU numbering begins. Start from 1 for a new catalogue, or from a higher number if you're continuing an existing system (e.g., start at 501 to avoid conflicts with existing SKUs).
Step 5 — Set Number of Digits
Choose how many digits the numeric suffix should have. Using 3 digits (001) supports up to 999 SKUs per category. Using 4 digits (0001) supports up to 9,999. Always pad to a fixed length so SKUs sort correctly alphabetically.
Step 6 — Set Quantity
Enter how many SKU codes you need to generate in this batch — from 1 to hundreds at once.
Step 7 — Generate, Copy, or Export
Click Generate SKUs to instantly produce all codes. Then:
- Copy All to paste directly into your spreadsheet or inventory system
- Export as CSV to download a file ready for bulk import into Shopify, WooCommerce, Amazon Seller Central, Tally, or any ERP
SKU Format Best Practices
A good SKU system is readable, consistent, and scalable. Follow these principles:
Keep It Short but Meaningful
Aim for 8–16 characters. Short enough to type quickly, long enough to carry useful information. Avoid verbose descriptions.
| Good SKU | Bad SKU |
|---|---|
SHOE-RUN-BLK-42 | RUNNING SHOES BLACK SIZE 42 |
ELEC-HDMI-001 | hdmicable1 |
FURN-CHAIR-003 | FurnitureChairOfficeBlackLeather003 |
- Use All Uppercase — SKUs should always be uppercase. Mixed-case creates confusion and potential duplicate detection issues in databases.
- No Spaces or Special Characters — Only use letters, numbers, hyphens, or underscores. Spaces, slashes, and symbols break imports in most inventory and e-commerce systems.
- Pad Numbers to Fixed Length — Always zero-pad your numeric suffix:
001,002... not1,2. - Be Consistent — Once you've set a format, stick to it. Mixing formats creates chaos in reports and imports.
- Don't Encode the Price — Prices change. Don't include price information in your SKU — use separate fields for that.
- Plan for Variants — If your products come in different sizes, colours, or materials, build that into your SKU structure from the start:
PREFIX-CATEGORY-COLOUR-SIZE-NUMBER
SKU vs Barcode vs UPC — What's the Difference?
Many business owners confuse SKUs with barcodes. Here's a clear comparison:
| Feature | SKU | Barcode (EAN/UPC) | ISBN |
|---|---|---|---|
| Created by | You (internal) | Standards body | Publishers |
| Format | Alphanumeric, custom | Numeric only | 13 digits |
| Unique to | Your business | Globally | Book title/edition |
| Required for retail shelves | No | Yes (large retailers) | Yes (books) |
| Required for online selling | Recommended | Sometimes | For books |
| Carries meaning | Yes (your system) | No (just a number) | Partial |
| Used for | Internal tracking | Checkout scanning | Book catalogues |
Key takeaway: SKUs are your internal coding system. Barcodes (EAN-13, UPC-A) are global identifiers required by retailers and marketplace platforms. Most businesses use both — the SKU for internal tracking and the barcode for external scanning. This tool generates SKUs; for barcodes, see the ISBN Barcode Generator.
Industries & Use Cases
SKU generators are useful across a wide range of industries:
- Retail & Fashion — Generate SKUs for clothing, footwear, and accessories by category, colour, and size.
- Electronics & Gadgets — Categorise by product type, brand, model, and specification. Example:
ELEC-USB-C-PWR-001. - Food & Grocery — Assign SKUs to product types, packaging size, and flavour variants.
- E-Commerce (Shopify, WooCommerce, Amazon) — All major platforms require or recommend SKUs for product variants. Generate in bulk and import directly via CSV.
- Wholesale & B2B Distribution — Standardise product codes across your catalogue to reduce purchase order errors.
- Manufacturing & Warehousing — Track raw materials, semi-finished goods, and finished products across production stages.
- Pharmaceuticals & Healthcare — Assign SKUs to medicines, devices, and consumables for batch tracking.
- Books & Publishing — Create internal SKUs for editions and formats alongside standard ISBNs.
How to Import SKUs into Popular Platforms
Once you've generated your SKUs and exported the CSV, here's how to use them:
- Shopify — Go to Products → Import → Download the CSV template → Paste your SKUs in the "Variant SKU" column → Upload.
- WooCommerce — Use the Product CSV Import Suite or a plugin like "WP All Import" to map your SKU column during import.
- Amazon Seller Central — In your inventory flat file template, the "seller-sku" column is where your SKU goes (also called Merchant SKU).
- Flipkart Seller Hub — Use the bulk upload template and map your SKU to the "SKU ID" or "Seller SKU" field.
- Tally ERP / Tally Prime — Import stock items using the Tally XML/CSV import feature, mapping your SKU to the stock item code field.
- Excel / Google Sheets — Paste or import the CSV directly. Add your own columns for product name, price, stock quantity, supplier, etc.
Tips for Building a Scalable SKU System
- Start with a master spreadsheet — Map out your product categories, variants, and naming conventions before generating.
- Use a hierarchy — A three-level structure works well:
[BRAND/PREFIX] - [CATEGORY] - [VARIANT/NUMBER] - Reserve number ranges per category — Electronics gets 1000–1999, Clothing gets 2000–2999. This prevents number overlap.
- Document your system — Write down the rules for your SKU format so team members and suppliers can follow them.
- Review periodically — As your product range evolves, revisit your SKU structure. It's easier to refactor early than to overhaul thousands of established SKUs.
Need unique serial numbers for individual units? Try our Serial Number Generator. Reference SKUs on client invoices with our Invoice Generator, or include them on shipping labels.
Frequently Asked Questions
Is this SKU generator free?
Yes, completely free. There are no usage limits, no premium plans, and no credit system. Generate as many SKU codes as you need at no cost.
Do I need to sign up or create an account?
No. There's no registration, login, or email required. Open the tool, configure your SKU format, generate, and export — that's it.
What is a SKU code?
A SKU (Stock Keeping Unit) is a unique alphanumeric code assigned to a product for internal identification and inventory tracking. Unlike a barcode (which is a globally standardised number), a SKU is created by you and follows your own naming convention. It typically encodes category, variant, and a sequential number.
What's the difference between a SKU and a barcode?
A SKU is your internal product code — created by you, meaningful to your business, and used for internal inventory management. A barcode (EAN-13 or UPC-A) is a globally standardised numeric identifier used for scanning at POS terminals and required by major retailers. Most businesses use both — SKU for internal tracking, barcode for external retail.
How many SKU codes can I generate at once?
You can generate as many as you need in a single batch by adjusting the Quantity field. There's no hard cap — whether you need 10 or 10,000 SKUs, the tool handles it.
Can I export the generated SKUs to a CSV file?
Yes. After generating, click the CSV button to download a CSV file containing all your SKU codes. This file can be imported directly into Shopify, WooCommerce, Amazon Seller Central, Tally, or opened in Excel/Google Sheets.
What should I use as a prefix?
The prefix is typically your brand initials, store code, or product line identifier. For example: TG for Tools Galaxio, SS25 for a Spring/Summer 2025 collection, or WH for a warehouse location. Keep it 2–5 characters.
What should I use as a category code?
The category code identifies the product type or department. Examples: SHOE, ELEC, FURN, BOOK, APPRL. Aim for 3–6 uppercase characters that clearly indicate the category at a glance.
Which separator should I use between SKU segments?
The hyphen (-) is the most widely used separator and is accepted by virtually all e-commerce platforms and inventory systems. Underscores (_) are also safe. Avoid spaces and special characters, as these can cause import errors on many platforms.
What does "number of digits" mean?
This controls how many digits the sequential number at the end of the SKU has. Choosing 3 digits means your SKUs end in 001, 002, 003, etc. Choosing 4 digits gives you 0001, 0002, etc. Use fixed-length padding so SKUs sort correctly in spreadsheets.
Can I generate SKUs for product variants (size, colour)?
This tool generates a sequential batch of SKUs with a consistent prefix and category. For variant-level SKUs (e.g., the same shirt in 5 colours and 4 sizes), set a unique category code or prefix per variant group, then generate a batch for each. For example, generate SHIRT-BLU SKUs and SHIRT-RED SKUs separately.
Can I use numbers only in my SKUs (no letters)?
You can leave the prefix and category fields blank or use numbers if your system requires it. However, alphanumeric SKUs are strongly recommended — pure numeric codes are harder to read, less meaningful, and more error-prone in manual processes.
Can I import the generated SKUs into Shopify?
Yes. Export the CSV from this tool, then go to Shopify Admin → Products → Import. Download Shopify's CSV template, paste your SKUs into the "Variant SKU" column, and upload. For new products, you'll need to fill in other required fields (title, price, etc.) alongside your SKUs.
Can I import SKUs into Amazon Seller Central?
Yes. In Amazon's inventory flat file templates, there's a "seller-sku" column. Copy your generated SKUs into that column in the relevant flat file for your category and upload via Add Products via Upload.
What makes a good SKU system?
A good SKU system is: consistent (same format for every product), meaningful (encodes category/variant), short (8–16 characters), uppercase only, free of spaces/special characters, and padded to fixed numeric length. It should also be scalable — built to accommodate growth in your product range without needing restructuring.
Should SKUs include the product price or supplier name?
No. Prices and supplier relationships change frequently. Encoding them in a SKU creates maintenance headaches — you'd need to rename SKUs every time a price changes or you switch suppliers. Keep SKUs stable identifiers; store price and supplier information in separate fields.
What's the ideal length for a SKU?
8 to 16 characters is the widely recommended range. Long enough to be meaningful and unique, short enough to type quickly and display properly in reports and labels. Anything over 20 characters becomes cumbersome.
Can I use this tool to regenerate SKUs if I already have some?
Yes. Set the starting number to continue from where your existing SKUs left off. For example, if your last SKU ended in 055, set the start number to 56 to generate the next batch seamlessly.
Do the generated SKUs get saved anywhere?
No. The tool runs entirely in your browser. Generated SKUs are not stored on any server. Once you close or refresh the page, the data is gone — so make sure to copy or download your SKUs before leaving.
Can I use these SKUs on multiple platforms simultaneously?
Yes, and that's one of the biggest advantages of having your own SKU system. You can use the same SKU on your Shopify store, Amazon listing, WooCommerce site, and internal spreadsheet — creating a single source of truth for product identification across all channels.