What is Buffer Quantity?
Buffer Quantity is a per-SKU safety-stock setting that tells Luminous how much inventory to hold back before publishing available stock to an external sales channel (such as Shopify). Instead of showing your full available quantity on a channel, Luminous subtracts the buffer first, so a reserve of physical stock is always protected from being sold online.
This is useful for preventing overselling, accommodating warehouse inaccuracies, or reserving stock for non-channel orders.
Buffer Types
Luminous supports two ways to express a buffer:
| Type | How it works | Example |
|---|---|---|
| Fixed | Subtracts a set number of units from the quantity Luminous will push to the channel. | Available: 100, Buffer: 10 → Channel sees 90 |
| Percent | Subtracts a percentage of the available quantity (rounded up to the nearest whole unit). | Available: 100, Buffer: 10% → Channel sees 90 |
Fixed is the default type when none is explicitly selected.
How the Buffer is Applied
Every time Luminous calculates the quantity to push to a channel, it:
- Starts with your sellable quantity (on-hand minus pending orders and any unfulfillable stock, depending on your settings).
- Calculates the effective buffer based on the type you chose.
- Subtracts the effective buffer from the sellable quantity.
- If the result is zero or negative, Luminous pushes 0 to the channel — the published quantity never goes below zero under normal channel-push conditions.
So if your buffer equals or exceeds the available stock, the channel will show zero units available even if you have physical inventory on hand.
Where to Set Buffer Quantity
For an Integration Account (e.g., Shopify)
- Click your name in the top-right corner and select Settings / Integrations.
- Open the integration account and select Manage Products.
- Find the SKU in the list, click into the Buffer Quantity field, and enter your desired value.
For a Channel's Product Mapping Grid
- Navigate to Manage → Channels in Luminous.
- Open the channel and go to the product mapping table.
- The table includes a Buffer Quantity column and a Buffer Type column — click either cell to edit the value inline.
Channel-level overrides: If a channel has its own buffer setting for a SKU, that value takes precedence over the integration-level default.
Tips
- A buffer of 0 (or no buffer set) means Luminous pushes your full available quantity to the channel.
- Use Fixed when you want to hold back a constant number of units regardless of inventory levels.
- Use Percent when you want the reserve to scale automatically as your stock fluctuates.
- You can review exactly how a stock push quantity was calculated — including how the buffer was applied — using the Stock Push Explanation dialog on the channel product mapping screen.
- For step-by-step instructions on creating a buffer, see Creating an Inventory Buffer.