If you've ever built a Tableau dashboard and wondered:

"Why isn't my calculation changing when I apply a filter?"

or

"How can I calculate something at a different level than what's shown in the view?"

then you need to understand two things:

1. Tableau's Order of Operations
2. Level of Detail (LOD) Expressions

So, What is an LOD?

LOD stands for Level of Detail.

It allows you to tell Tableau:

"Calculate this metric at a different level than what I'm showing in the view."

Imagine you're looking at sales by Category.

Without an LOD:

Furniture → £700K

Technology → £800K

Office Supplies → £600K

Tableau calculates everything at the Category level because that's what is displayed.

With an LOD, you can ask:

"Calculate sales per customer even though I'm only showing categories."

FIXED LOD

FIXED tells Tableau exactly which level to use.

{ FIXED [Customer Name] : SUM([Sales]) }

What Tableau does:

Customer John → £5,000

Customer Sarah → £8,000

Customer Mike → £3,000

Even if Customer Name is not visible in the chart, Tableau still calculates the result at the customer level.

INCLUDE LOD

INCLUDE adds more detail than what's currently visible.

{ INCLUDE [Customer Name] : SUM([Sales]) }

View:

Category

Furniture

Technology

Office Supplies

Tableau calculates behind the scenes:

Category + Customer

Then rolls everything back up to Category.

EXCLUDE LOD

EXCLUDE removes detail from the current view.

{ EXCLUDE [Sub-Category] : SUM([Sales]) }

View:

Category

Sub-Category

Sales

Even though Sub-Category is displayed, Tableau ignores it for the calculation.

When Should I Use Each LOD?

Use FIXED when you want a fixed business metric

-Total Sales per Customer

-Customer Lifetime Value

-First Purchase Date

Use INCLUDE when you need more granularity

-Average Sales per Customer

-Average Sales per Order

Use EXCLUDE when you need higher-level totals

-Percent of Category

-Share of Region

-Contribution Analysis

So, what is Order of Operations?

Many Tableau problems happen because Tableau does not execute everything at the same time.

Instead, Tableau follows a specific sequence:

The most important thing to remember is:

FIXED LODs are calculated before Dimension Filters.

INCLUDE and EXCLUDE LODs are calculated after Dimension Filters.

This single concept explains most LOD behavior.

How a Dimension Filter Affects a FIXED LOD

Imagine you have sales data:

• John sold £100 in the East region.
• John sold £200 in the West region.

You create this FIXED LOD:

{ FIXED [Customer Name] : SUM([Sales]) }

Tableau calculates:

John = £300

because it adds all of John's sales together.

Now you add a Dimension Filter:

Region = West

You might expect John's sales to become:

John = £200

But they don't.

The result is still:

John = £300

Why?

Because Tableau works in this order:

1. Calculate FIXED LOD2. Apply Dimension Filter

So Tableau calculates John's total sales (£300) before looking at the Region filter.

What About INCLUDE and EXCLUDE?

INCLUDE and EXCLUDE work differently.

For them, Tableau works like this:

Apply Dimension Filter
↓
Calculate LOD

So if you filter:

Region = West

Tableau removes the East records first.

Then it performs the calculation.

As a result:

John = £200

The Rule to Remember

FIXED ignores Dimension Filters.

INCLUDE and EXCLUDE respect Dimension Filters.

This is the most important concept to understand when working with LODs in Tableau.