Editing Units and Conversions

InventoryUpdated October 5, 2026 · Reviewed by Peasy Team

After you create an item, you might need to update a unit name, change a conversion factor, or add a new size. Here's how to make those changes — and one important thing to watch out for.

How to Get There

Open any item from Buy > Items to buy or Sell > Items to sell, then edit the variant on the item detail page.

Editing a Buy or Sell Variant

To change the unit name or conversion factor on an existing variant:

  1. Go to the item's detail page.
  2. Open the Variants tab, then click the Unit cell for the buy or sell variant you want to edit.
  3. Update the unit name, conversion factor, or both.
  4. Click Save in the popover.

The update applies to future orders only — existing purchase orders and sales orders keep their original values.

Example: Your hot sauce supplier switched from 24-count cases to 30-count cases. Open the buy variant, change the conversion from 24 to 30, and save. Your next PO will use the new case size.

When a Conversion Cannot Be Changed in Place

If a connected source such as Shopify has posted inventory movements for the variant or one of its dependent variants, Peasy will not delete that history to change the conversion. Instead, the Transition to new variant dialog opens.

Review the change, then click Continue. Peasy will:

  • Mark the current variant as inactive so its inventory history remains intact.
  • Create a replacement variant with the corrected conversion.
  • Move future-facing records and mappings to the replacement.

The destructive repair option is no longer available after Peasy detects connected-source history. A conversion with only manually entered inventory history can still be repaired in place by an authorized admin.

When Two Variants Would Share a Unit Name

Two variants in the same item family can use the same unit name only if they also use the same conversion. Otherwise every "pick a unit" dropdown elsewhere in Peasy would have two options both labeled (for example) case and no way to tell them apart.

If you save a change that would leave your variant with the same unit name as another active variant in the family but a different conversion, Peasy blocks the save and shows an amber notice above the conversion fields. You have two ways to resolve it:

  • Rename this variant's unit. Use the Unit dropdown at the top of the same popover to pick a distinct name (e.g. case → pack). The pick is staged — it isn't saved until you click Save, so you can change the unit and the conversion together in one save.
  • Match the existing conversion. If you actually want this variant to be the same as the other one (e.g. you wanted pack = 6 jars to become case = 12 jars to match a sibling that's already case = 12 jars), set the conversion to match. The save will go through because the resulting state is consistent.

The notice doesn't appear when nothing has changed, when the unit name doesn't collide with another variant, or when the conversion already matches the existing variant.

Adding a New Variant

You can add buy or sell variants to any existing item:

  1. Go to Buy > Items to buy or Sell > Items to sell.
  2. Click the dropdown arrow next to + New Item.
  3. Select New Variant.
  4. Choose the parent item and enter the new unit name and conversion ratio.

Example: You sell honey in 12-oz jars but want to start offering a 32-oz bottle too. Add a new sell variant — both sizes share the same inventory pool.

Archiving a Variant

If you stop buying or selling a particular size, you can archive the variant. Historical records (purchase orders, sales orders, receives) are preserved — the variant just stops appearing in new orders.

Changing the Inventory Unit

Every item family has an Inventory Unit — the base unit at the root of its conversion chain. You'll see it labeled "Inventory Unit" on the item detail side panel, where you can rename it or swap it for a different unit.

When you open the Inventory Unit dropdown, the options are grouped:

  • Family units — units already used by variants in this product family.
  • All units — every other unit you've used elsewhere in your account.

Picking from Family units just swaps which variant's unit acts as the inventory unit. Picking from All units (or typing a new label and clicking Use) opens a popover with two choices:

  • Relabel — rename the existing inventory unit to the new label. Any sibling variants that share the old label with a 1:1 conversion get renamed in the same step, so a case → pack rename moves every matching variant in one atomic save.
  • Create new — keep the existing inventory unit and add a new variant with the new unit and a conversion ratio.

Caution: The Inventory Unit is the foundation all your conversions are built on. Changing it does not automatically convert your existing quantities — the number stays the same, but its meaning changes. If you have 50 "lbs" and change the unit to "kg," Peasy will show 50 kg — not the converted amount.

If your family has no inventory history yet, changing the Inventory Unit is safe — just update it from the item side panel.

If your family already has inventory history, it's best to create a new family with the correct Inventory Unit and adjust your inventory over. This avoids mismatched records and keeps your history clean.

Good to Know

  • Background refreshes keep your draft. If inventory refreshes while the Unit editor is open, your unsaved unit and conversion changes stay in the popover.
  • Edits don't rewrite order history. Past POs, SOs, and receives keep their original values. If connected-source inventory history would be affected, Peasy preserves it by transitioning to a replacement variant.
  • You can have multiple buy and sell variants. Buy flour in 50-lb bags and 5-lb bags from different suppliers — both draw from the same inventory pool.
  • Archiving is reversible. Archived variants can be restored if you need them again.
  • "Another change to this item family is still in progress." Two people (or two tabs) edited the same item family at the same moment. Nothing was saved and nothing was lost — wait a moment and save again.

Related