---
title: "About derived fields | Lansweeper Platform"
slug: "about-derived-fields"
description: "Learn how derived fields in Lansweeper add calculated columns to an asset dataset, computing values from existing fields each time a dashboard loads."
updated: 2026-07-03T13:23:08Z
published: 2026-07-03T13:23:08Z
canonical: "docs.lansweeper.com/about-derived-fields"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://docs.lansweeper.com/llms.txt
> Use this file to discover all available pages before exploring further.

# About derived fields

Derived fields are calculated values you can add to an asset dataset. Rather than storing a value directly, a derived field calculates its result from existing field values each time a dashboard loads.

## How derived fields work

Each derived field uses an expression: a formula in Lansweeper's expression language. When you load a dashboard, Lansweeper evaluates that expression for each row in your dataset and returns the result as a new column alongside your other asset fields.

Expressions are row-level. Lansweeper evaluates each row independently, using only that row's field values as inputs.

## When to use derived fields

Derived fields are useful when you need to:

- Combine values from multiple fields into a single display column (for example, joining an asset name and location)
- Convert or reformat existing data (for example, converting a date to a readable string, or changing a unit of measurement)
- Apply conditional logic to categorize assets based on field values
- Calculate a value from numeric fields without modifying the underlying data

## Limitations

Because derived fields work row by row, they have some constraints:

- **No aggregations.** You can't sum, count, or average across multiple rows.
- **No cross-row references.** Each expression sees only the current row.
- **No joins.** You can't pull data from another dataset into a derived field.
- **No references to other derived fields.** Expressions can only reference base dataset fields.
- **No interval arithmetic.** `INTERVAL` expressions aren't yet supported.

If you need aggregations or cross-dataset logic, use dashboard-level calculations or filters instead.

## Permissions

Derived fields use 4 separate permission toggles, each controlled per role:

| Permission | What it allows |
| --- | --- |
| View | See derived fields in dashboards |
| Create | Add new derived fields to a dataset |
| Edit | Modify existing derived fields |
| Delete | Remove derived fields |

Disabling **View** for a role disables all other derived field permissions for that role.

By default, the **Administrator** and **Manage Assets** roles have all 4 permissions enabled.

## Derived fields in dashboards

A derived field is part of the asset dataset. You add it to a dashboard through the dashboard editor, the same way you add any other asset field.

Custom fields work the same way. Any custom or derived field you create is available in the asset dataset, so you can pull it into dashboards that use that dataset.

For the steps, see [Add a derived field to a dashboard](/docs/create-and-manage-derived-fields#add-a-derived-field-to-a-dashboard).

## Current scope

Derived fields are currently available for the **asset dataset** only. Support for additional datasets will follow in future releases.

Derived fields are available on **Lansweeper Platform** only.

## Next steps

- [Custom fields](/docs/custom-fields)
- [Create and manage derived fields](/docs/create-and-manage-derived-fields)
- [Derived fields expression language reference](/docs/derived-fields-expression-language-reference)
- [Derived fields function reference](/docs/derived-fields-function-reference)