Track every part,
down to the last screw.

To add a new inventory item, navigate to the Inventory tab in the sidebar and click the + button, or press ⌘N on macOS. On iPad, tap the + button in the top toolbar.

The item form includes the following fields:

• Name (required) — the display name of the item (e.g., "Seymour Duncan SH-1n")
• SKU — auto-generated based on your SKU pattern, or enter a custom value
• Internal SKU — your own internal reference number, independent of the auto-generated SKU
• Barcode — UPC, Code128, or QR code value for scanning
• Category — top-level grouping (e.g., Pickups, Hardware, Strings)
• Subcategory — second-level grouping within the category
• Item Type — third-level classification for fine-grained organization
• Quantity — current stock count
• Unit Cost — what you pay per unit from your supplier
• Sale Price — what you charge your customers
• Reorder Point — the stock level at which a low-stock alert triggers
• Reorder Quantity — how many you typically order when restocking
• Location — where the item lives in your shop (e.g., "Shelf B3", "Drawer 7")
• Description — detailed notes about the item
• Photo — a visual reference image (see Item Photos below)
• Unit of Measure — how the item is counted or sold (see Units of Measure below)
• Units per Package — how many individual pieces come in one package

Fill in at least the name and category, then click Save. The item appears immediately in your inventory list.

Click any item in the inventory list to open its detail view. All fields are editable inline. Make your changes and click Save, or press ⌘S on macOS.

To delete an item, open it and click the Delete button at the bottom of the form. You will be asked to confirm before the item is permanently removed.

• Select multiple items using the checkboxes in the list view for bulk editing
• Bulk edit lets you change category, subcategory, location, and other shared fields across all selected items at once
• Bulk delete removes all selected items after confirmation

StringsTheory can automatically generate SKUs for new items based on a pattern you configure in Settings → SKU Format. There are four built-in patterns:

• Auto — generates a sequential numeric SKU automatically (e.g., 000001, 000002)
• Category-Type-Product — combines your category, item type, and product abbreviation (e.g., HW-SCR-MACH)
• Product CamelCase — derives the SKU from the item name in camel case (e.g., SeymourDuncanSH1n)
• Custom — build your own pattern using placeholders

When using the Custom pattern, you can combine the following placeholders:

• {CAT} — abbreviated category name
• {TYPE} — abbreviated item type
• {PROD4} — first four characters of the product name
• {NUM6} — six-digit sequential number

For example, a custom pattern of {CAT}-{PROD4}-{NUM6} might produce HW-MACH-000042 for a hardware item named "Machine Head Tuner".

StringsTheory uses a three-level taxonomy to organize your inventory: Category, Subcategory, and Item Type. Configure all three levels in Settings → Categories.

• Categories are your top-level groupings (e.g., Pickups, Hardware, Strings, Tools, Electronics)
• Subcategories nest inside a category (e.g., under Hardware: Screws, Tuners, Bridges, Nuts & Saddles)
• Item Types provide the finest level of classification (e.g., under Screws: Pickguard Screws, Pickup Ring Screws, Truss Rod Cover Screws)

To add a new category, go to Settings → Categories, click + Add Category, and enter the name. You can then add subcategories and item types within each category.

When you assign a category to an inventory item, the subcategory picker automatically filters to show only subcategories that belong to that category. The same cascading behavior applies to item types.

Each inventory item can have a unit of measure (UOM) that describes how it is counted, stored, or sold. Select the UOM when creating or editing an item. The available units are:

• ea (each) — individual pieces, the default
• box — a box of items
• bag — a bag of items
• case — a full case
• roll — a roll of material (e.g., shielding tape)
• spool — a spool of wire or string
• pack — a pack of items
• pair — sold in pairs (e.g., strap buttons)
• set — a complete set (e.g., a set of six tuners)
• ft — measured in feet (e.g., hookup wire)
• m — measured in meters
• lb — measured in pounds
• kg — measured in kilograms
• oz — measured in ounces
• custom — define your own unit label

When you set Units per Package alongside a UOM, StringsTheory automatically calculates the cost per piece. For example, if you buy a box of 100 screws for $12.00 and set units per package to 100, the cost per piece displays as $0.12. This helps you understand your true per-unit cost when you buy in bulk.

Never run out of critical parts again. Set a Reorder Point on any item to define the minimum stock level before you need to reorder. When the item's quantity drops to or below this threshold, several things happen:

• The item row in the inventory list is highlighted in red so it stands out visually
• The Dashboard shows a count of all low-stock items in the summary cards
• You can filter the inventory list to show only low-stock items for quick review

The Reorder Quantity field is a reference value that records how many units you typically order from your supplier. This is purely informational and helps you remember your standard order size when it is time to restock.

The Location field is a free-text field where you describe where an item lives in your shop. Use whatever naming convention works for your space — shelf numbers, drawer labels, room names, or bin codes.

• Examples: "Shelf A2", "Parts Drawer 7", "Back Room - Left Wall", "Bin #142"
• Location is searchable — type a location name in the search bar to find all items stored there
• Use bulk edit to update the location for multiple items at once when you reorganize your shop

Add a photo to any inventory item for quick visual identification. The process differs slightly between platforms:

• On iPad: Tap the photo area in the item form to open the camera for a live capture, or choose an existing image from your photo library
• On macOS: Click the photo area to open a file picker and select an image from your Mac

Photos are automatically compressed to a maximum of 800 pixels wide and saved as JPEG to keep your database size manageable. The compressed image is stored directly with the item record, so it syncs across devices if you have cloud sync enabled on the Annual plan.

Photos appear as thumbnails in the inventory list view and at full size in the item detail view. The list uses background image decoding so scrolling stays smooth even with hundreds of items.

StringsTheory supports Code128, QR, and UPC barcode formats. Use barcode scanning to speed up inventory lookups and item creation.

• Find an item: Tap the barcode scanner icon in the Inventory toolbar and scan a barcode. If an item with that barcode already exists, it opens immediately
• Create a new item: If no matching item is found, StringsTheory offers to create a new item with the scanned barcode pre-filled in the barcode field

On iPad, scanning uses the device camera. On macOS, you can use a USB or Bluetooth barcode scanner — the scanned value is entered as keyboard input into the search field.

If you sell items at both wholesale and retail, StringsTheory lets you link a wholesale item to its retail counterpart. When a wholesale item is sold or its quantity decreases, the linked retail item's quantity is automatically deducted as well.

• Open the item you want to flag as wholesale
• Enable the Wholesale toggle
• Select the linked retail item from the picker
• When the wholesale item's stock changes, the retail item updates automatically

This is useful for shops that sell both to other businesses (wholesale) and directly to customers (retail) from the same physical stock.

Mark an item as a component when it is a raw material or sub-part used in building assembled products. Component items are used in Bill of Materials (BOM) to define what goes into a finished product.

• Open the item and enable the Is Component toggle
• Fill in the component data fields that appear — these provide additional metadata relevant to manufacturing and assembly
• The item can now be referenced in BOM entries as a line-item ingredient

Flagging items as components helps you separate raw materials from finished goods in your inventory. You can filter the inventory list to show only components or only non-components, making it easier to manage your shop's supply chain.

The search bar at the top of the Inventory list provides live filtering across multiple fields. Press ⌘F on macOS to focus the search bar instantly. On iPad, tap the search field at the top of the list.

• Search matches against item name, SKU, internal SKU, and barcode simultaneously
• Results update as you type with a 300ms debounce to keep the interface responsive
• Clear the search field to show all items again — on iPad, the clear button has an enlarged 44pt tap target for easy use

The Dashboard also has a global search that works across all sections. If you search from the Dashboard and select an inventory result, StringsTheory navigates directly to that item in the Inventory tab.