Unit Classes & Units of Measure
Overview
Unit Classes and Units of Measure work together to define how quantities are expressed throughout the inventory system — on item records, purchase orders, sales documents, and stock counts.
A Unit Class is a measurement category (for example, Quantity, Volume, Weight, Length). Each class contains one or more Units of Measure that belong to that category (for example, Pieces, Dozen, and Box all belong to the Quantity class). Every unit in a class is defined by its relationship to the class's base unit, so the system can always convert between them.
Unit Classes
The Unit Classes list is found at Setup → Measurement Management → Unit class in the left navigation.
The Unit Classes List
The left panel shows all active unit classes. Each row displays:
| Column | Description |
|---|---|
| Name | The measurement category (e.g. Quantity, Volume, Weight, Length) |
| Description | A short explanation of what the class covers |
Use the toolbar to manage classes:
| Action | Description |
|---|---|
| + New | Create a new unit class |
| Edit | Edit the selected class's name or description |
| Archive | Archive (soft-delete) the selected class |
| Archived unit classes | View and restore previously archived classes |
| Units of measure | Switch the right panel to show the units within the selected class |
Unit Class Details
Selecting a class from the list opens its details on the right:
| Field | Description |
|---|---|
| Unit class name | The display name for this measurement category |
| Description | Optional free-text description |
| Base unit | The reference unit for all conversion calculations in this class |
| Preferred display unit | The unit shown by default on item cards and reports |
When a unit class is first created, the system automatically creates a base unit and sets it as both the base unit and the preferred display unit. You can add more units and change the preferred display unit at any time, but the base unit is fixed after creation.
Creating a Unit Class
- Select + New in the toolbar.
- Fill in the fields:
- Unit class name (required) — the measurement category name. Maximum 100 characters. Must be unique.
- Description (optional) — what this class covers. Maximum 500 characters.
- Base unit name (required) — the name of the fundamental unit for this class. Maximum 100 characters.
- Base unit symbol (required) — the short symbol used in tables and labels (e.g.
pcs,ml,kg). Maximum 10 characters. Must be unique across all units. - Decimal precision (required) — the number of decimal places allowed when entering quantities in this unit. Must be between 0 and 10.
- Select Save.
The system creates the class and immediately creates the base unit you defined, assigning it as both the base unit and the preferred display unit.
Al Baraka sets up their Quantity class:
| Field | Value |
|---|---|
| Unit class name | Quantity |
| Description | Units for counting discrete items |
| Base unit name | Pieces |
| Base unit symbol | pcs |
| Decimal precision | 0 |
After saving, the Quantity class exists with Pieces as its base unit.
Editing a Unit Class
- Select the class from the list.
- Select Edit in the toolbar.
- Update the Name or Description as needed.
- Select Save.
The base unit and preferred display unit cannot be changed from the class edit form. To change the preferred display unit, manage it from the Units of measure view.
Archiving a Unit Class
Archiving removes a unit class from selection dropdowns throughout the system, but preserves all historical data. Any items that were previously assigned a unit class will continue to reference it — their records are not changed. The class simply becomes unavailable for new assignments.
- Select the class from the list.
- Select Archive in the toolbar.
- Confirm.
To view archived classes and restore them, select Archived unit classes in the toolbar.
Archiving a unit class also makes all of its units of measure unavailable for new assignments. Existing records are unaffected.
Units of Measure
To manage the units within a class, select the class from the list, then select Units of measure in the toolbar. The right panel switches to show a table of all active units in that class.
Viewing Units
In view mode, the table shows:
| Column | Description |
|---|---|
| Name | The full name of the unit (e.g. Pieces, Dozen) |
| Symbol | The short symbol used in documents and labels (e.g. pcs, dz) |
| Decimal precision | How many decimal places are allowed for quantities in this unit |
| Relative label | How one unit compares to the base unit (e.g. 12 pcs for Dozen) |
The Relative label is a human-readable summary of the conversion factor — it always shows the equivalent in the base unit.
Al Baraka's Quantity class units:
| Name | Symbol | Decimal precision | Relative label |
|---|---|---|---|
| Pieces | pcs | 0 | 1 pcs |
| Dozen | dz | 0 | 12 pcs |
How Conversion Factors Work
Every unit is defined by two things: a reference unit (another unit in the same class) and a factor to that reference unit. The system calculates the factor to the base unit automatically:
Factor to base unit = Factor to reference unit × Reference unit's factor to base unit
This chain means you can define units relative to any existing unit in the class — you do not have to always reference the base unit directly. The system traces the chain and computes the absolute factor for you.
Adding a Unit of Measure
When the Units of measure panel is in edit mode, a blank row appears at the top of the table for entering a new unit. The edit mode columns are:
| Column | Description |
|---|---|
| Name | Full name for the new unit |
| Symbol | Short symbol. Maximum 10 characters. Must be unique across all units system-wide. |
| Decimal precision | Decimal places allowed (0 – 10) |
| Factor to reference unit | How many reference units equal one of this new unit. Must be greater than 0. |
| Reference unit | Which existing unit in this class to use as the reference point |
Steps:
- Select the unit class from the list.
- Select Units of measure, then switch to edit mode.
- In the blank row at the top, fill in all columns.
- Select Save.
Al Baraka wants to receive perfume bottles by the dozen. They add:
| Name | Symbol | Decimal precision | Factor to reference unit | Reference unit |
|---|---|---|---|---|
| Dozen | dz | 0 | 12 | Pieces (pcs) |
Calculated factor to base: 12 × 1 = 12 pcs per dozen.
When a purchase order is received for 5 dz, the system records 60 pcs in stock.
Editing a Unit of Measure
- Select the class, then select Units of measure.
- Switch to edit mode.
- Update the Name, Decimal precision, Factor, or Reference unit for any existing row.
- Select Save.
A unit's Symbol cannot be changed after creation, as it is used as a permanent reference throughout existing records and reports.
Archiving a Unit of Measure
- Select the unit class from the list.
- Select Units of measure.
- Select the unit you want to archive.
- Select Archive in the toolbar.
Archived units are removed from dropdowns but remain in the database. Items and transactions that previously referenced an archived unit continue to display it — their records are not changed.
To view and restore archived units, select Archived units in the toolbar.
Validation Rules
Unit Class
| Field | Rule |
|---|---|
| Name | Required · Maximum 100 characters · Must be unique |
| Description | Optional · Maximum 500 characters |
| Base unit name | Required · Maximum 100 characters |
| Base unit symbol | Required · Maximum 10 characters · Must be unique across all units |
| Decimal precision | Required · Integer between 0 and 10 |
Unit of Measure
| Field | Rule |
|---|---|
| Name | Required · Maximum 100 characters |
| Symbol | Required · Maximum 10 characters · Must be unique across all units |
| Decimal precision | Required · Integer between 0 and 10 |
| Reference unit | Required · Must belong to the same unit class |
| Factor to reference unit | Required · Must be greater than 0 |
Planning Your Measurement Setup
A well-structured measurement setup makes purchasing, receiving, and reporting straightforward. Here is how Al Baraka organised theirs:
| Unit class | Base unit | Additional units | Used for |
|---|---|---|---|
| Quantity | Pieces (pcs, 0dp) | Dozen (dz, ×12), Box of 24 (box, ×24) | All countable finished goods and components |
| Volume | Millilitre (ml, 2dp) | Litre (L, ×1000), Fluid Ounce (fl oz, ×29.57) | Bulk essential oils, carrier oils, and liquid ingredients |
| Weight | Gram (g, 3dp) | Kilogram (kg, ×1000), Milligram (mg, ×0.001) | Solid raw materials, resins, and waxes |
| Length | Millimetre (mm, 0dp) | Centimetre (cm, ×10), Metre (m, ×1000) | Ribbon, label stock, and packaging film |
Define the base unit at the smallest practical granularity — for volume this is millilitres, not litres. This gives you the most flexible conversion chain and prevents rounding errors when converting between units.