Essential Tableau Formulas (and Their Power BI DAX Equivalents) for Data Analytics

For analysts transitioning from Tableau to Power BI (or vice versa), here are the most common Tableau calculations with their DAX counterparts in Power BI:

1. Basic Aggregations

Tableau (Table Calculation)

SUM([Sales])
AVG([Profit])
COUNTD([Customer ID])

Power BI (DAX)

Total Sales = SUM(Sales[Amount])
Average Profit = AVERAGE(Sales[Profit])
Unique Customers = DISTINCTCOUNT(Customers[CustomerID])

2. Conditional Logic

Tableau (IF/THEN)

IF [Sales] > 1000 THEN "High" ELSE "Low" END

Power BI (IF/SWITCH)

Sales Tier = 
IF(
    [Total Sales] > 1000, 
    "High", 
    "Low"
)
-- OR for multiple conditions:
Sales Category = 
SWITCH(
    TRUE(),
    [Total Sales] > 5000, "Premium",
    [Total Sales] > 1000, "Standard",
    "Basic"
)

3. Date Calculations

Tableau (DATE functions)

DATEADD('month', -1, [Order Date])
DATEDIFF('day', [Start Date], [End Date])

Power BI (DATEADD/DATEDIFF)

Previous Month Sales = 
CALCULATE(
    [Total Sales],
    DATEADD(Calendar[Date], -1, MONTH)
)

Days to Deliver = 
DATEDIFF(
    Orders[OrderDate],
    Orders[DeliveryDate],
    DAY
)

4. Level of Detail (LOD)

Tableau (FIXED)

{FIXED [Region] : SUM([Sales])}

Power BI (CALCULATE + ALL/ALLEXCEPT)

Sales by Region = 
CALCULATE(
    [Total Sales],
    ALLEXCEPT(Sales, Geography[Region])
)

5. Window Calculations

Tableau (WINDOW functions)

WINDOW_AVG(SUM([Sales]), -2, 0) -- 3-month moving avg

Power BI (Moving Average)

3 Month Moving Avg = 
AVERAGEX(
    DATESINPERIOD(
        Calendar[Date],
        LASTDATE(Calendar[Date]),
        -3,
        MONTH
    ),
    [Total Sales]
)

6. String Manipulation

Tableau (STRING functions)

LEFT([Product Code], 3)
CONTAINS([Product Name], "Pro")

Power BI (Text functions)

Product Category = LEFT(Products[ProductCode], 3)

Is Professional = 
CONTAINSSTRING(Products[ProductName], "Pro")

7. Lookup Values

Tableau (LOOKUP)

LOOKUP(SUM([Sales]), -1) -- Previous row

Power BI (EARLIER/PREVIOUSMONTH)

dax

Copy

Prev Month Sales = 
CALCULATE(
    [Total Sales],
    PREVIOUSMONTH(Calendar[Date])
)

8. Percent of Total

Tableau (Quick Table Calc)

SUM([Sales]) / TOTAL(SUM([Sales]))

Power BI (DIVIDE + ALL)

% of Total Sales = 
DIVIDE(
    [Total Sales],
    CALCULATE([Total Sales], ALL(Sales))
)

Key Differences to Remember

Pro Tips for Transitioning

1. Use Power BI's “Quick Measures” for Tableau-like calculations
2. Master CALCULATE() – It's Power BI's equivalent of Tableau's context adjustments
3. Build a proper date table – Unlike Tableau, Power BI needs this for time intelligence

Need help converting a specific Tableau calc to DAX? Share it below!