InvenTree/docs/docs/concepts/parameters.md

---
title: Parameters
---

## Parameters

A *parameter* describes a particular "attribute" or "property" of a specific object in InvenTree. Parameters allow for flexible and customizable data to be stored against various InvenTree models.

!!! note "Business Logic"
    Parameters are not used for any core business logic within InvenTree. They are intended to provide additional metadata for objects, which can be useful for documentation, filtering, or reporting purposes.

Parameters can be associated with various InvenTree models.

### Parameter Tab

Any model which supports parameters will have a "Parameters" tab on its detail page. This tab displays all parameters associated with that object:

{{ image("concepts/parameter-tab.png", "Part Parameters Example") }}

## Parameter Templates

Parameter templates are used to define the different types of parameters which are available for use. The following attributes are defined for a parameter template:

| Attribute | Description |
| --- | --- |
| Name | The name of the parameter template (*must be unique*) |
| Description | Optional description for the template |
| Units | Optional units field (*must be a valid [physical unit](#parameter-units)*) |
| Model Type | The InvenTree model to which this parameter template applies (e.g. Part, Company, etc). If this is left blank, the template can be used for any model type. |
| Choices | A comma-separated list of valid choices for parameter values linked to this template. |
| Checkbox | If set, parameters linked to this template can only be assigned values *true* or *false* |
| Selection List | If set, parameters linked to this template can only be assigned values from the linked [selection list](#selection-lists) |

{{ image("concepts/parameter-template.png", "Parameters Template") }}

### Create Template

Parameter templates are created and edited via the [admin interface](../settings/admin.md).

To create a template:

- Navigate to the "Settings" page
- Click on the "Part Parameters" tab
- Click on the "New Parameter" button
- Fill out the `Create Part Parameter Template` form: `Name` (required) and `Units` (optional) fields
- Click on the "Submit" button.

An existing template can be edited by clicking on the "Edit" button associated with that template:

{{ image("part/parameter_template_edit.png", "Edit Parameter Template") }}

### Create Parameter

After [creating a template](#create-template) or using the existing templates, you can add parameters to any part.

To add a parameter, navigate to a specific part detail page, click on the "Parameters" tab then click on the "New Parameters" button, the `Create Part Parameter` form will be displayed:

{{ image("part/create_part_parameter.png", "Create Part Parameter Form") }}

Select the parameter `Template` you would like to use for this parameter, fill-out the `Data` field (value of this specific parameter) and click the "Submit" button.

## Parametric Tables

Parametric tables gather all parameters from all objects of a particular type, to be sorted and filtered.

Tables views which support parametric filtering and sorting will have a "Parametric View" button above the table:

{{ image("concepts/parametric-parts.png", "Parametric Parts Table") }}

### Sorting by Parameter Value

The parametric parts table allows the returned parts to be sorted by particular parameter values. Click on the header of a particular parameter column to sort results by that parameter:

{{ image("part/part_sort_by_param.png", "Sort by Parameter") }}

### Filtering by Parameter Value

The parametric parts table allows the returned parts to be filtered by particular parameter values. Click on the {{ icon("filter") }} button associated with the particular parameter, and enter the value you wish to filter against:

{{ image("part/filter_by_param.png", "Filter by Parameter") }}

The available filter options depend on the type of parameter being filtered. For example, a parameter with a limited set of choices will allow you to filter by those choices, while a numeric parameter will allow you to filter against a specific value and operator (e.g. greater than, less than, etc.).

#### Filtering by Multiple Parameters

Multiple parameters can be used to filter the parametric table. Simply add a new filter for each parameter you wish to filter against. The results will be filtered to include only parts which match *all* of the specified filters.

Each parameter column indicates whether a filter is currently applied:

{{ image("part/multiple_param_filters.png", "Multiple Parameter Filters") }}

#### Multiple Filters Against the Same Parameter

It is possible to apply multiple filters against the same parameter. For example, you can filter for parts with a *Resistance* parameter greater than 10kΩ and less than 100kΩ by adding two filters for the *Resistance* parameter:

{{ image("part/multiple_filters_same_param.png", "Multiple Filters on Same Parameter") }}

#### Unit-Aware Filtering

When filtering against a parameter which has a unit defined, you can specify the value in any compatible unit. The system will automatically convert the value to the base unit defined for that parameter template.

For example, to show all parts with a *Resistance* parameter of greater than 10kΩ, you can enter `10k` or `10000` in the filter field, and the system will correctly interpret this as 10,000 ohms.

{{ image("part/filter_with_unit.png", "Unit Aware Filters") }}

#### Removing Filters

To remove a filter against a given parameter, click on the {{ icon("circle-x", color='red') }} button associated with that filter:

{{ image("part/remove_param_filter.png", "Remove Parameter Filter") }}

#### Available Filter Operators

The following filter operators are available for parameter filtering:

- `=`: Equal to
- `>`: Greater than
- `>=`: Greater than or equal to
- `<`: Less than
- `<=`: Less than or equal to
- `!=`: Not equal to
- `~`: Contains (for text parameters)

## Parameter Units

The *units* field (which is defined against a [parameter template](#parameter-templates)) defines the base unit of that template. Any parameters which are created against that unit *must* be specified in compatible units.

The in-built conversion functionality means that parameter values can be input in different dimensions - *as long as the dimension is compatible with the base template units*.

!!! info "Read Mode"
    Read more about how InvenTree supports [physical units of measure](../concepts/units.md)

### Incompatible Units

If a part parameter is created with a value which is incompatible with the units specified for the template, it will be rejected:

{{ image("part/part_invalid_units.png", "Invalid Parameter Units") }}

This behaviour can be disabled if required, so that any parameter value is accepted.

### Parameter Unit Sorting

Parameter sorting takes unit conversion into account, meaning that values provided in different (but compatible) units are sorted correctly:

{{ image("part/part_sorting_units.png", "Sort by Parameter Units") }}

### Selection Lists

Selection Lists can be used to add a large number of predefined values to a parameter template. This can be useful for parameters which must be selected from a large predefined list of values (e.g. a list of standardized color codes). Choices on templates are limited to 5000 characters, selection lists can be used to overcome this limitation.

It is possible that plugins lock selection lists to ensure a known state.


Administration of lists can be done through the Part Parameter section in the [Admin Center](../settings/admin.md#admin-center) or via the API.