Power BI DAX Functions Every Analyst Must Know (2026 Guide)

DAX (Data Analysis Expressions) is the formula language that turns a basic Power BI report into a powerful analytics tool. These are the functions that matter most for real jobs.

Essential Aggregation Functions

  • SUM / AVERAGE / COUNT for totals and counts
  • SUMX / AVERAGEX row-by-row iterators for calculated aggregations
  • DISTINCTCOUNT for unique counts such as unique customers

The Most Important Function: CALCULATE

CALCULATE changes the filter context of a calculation and is the foundation of advanced DAX. Master it and most other patterns become easy.

Time Intelligence

TOTALYTD and TOTALMTD for year-to-date and month-to-date, SAMEPERIODLASTYEAR for year-over-year, and DATEADD to shift dates for trend analysis.

How to Practice

Build a sales dashboard and recreate each function with real data. GloryTecks' [Power BI course in Hyderabad](/courses/power-bi) covers DAX end-to-end with business datasets, and the [Data Analytics course](/courses/data-analytics) adds SQL and Python for analytics. Book a free demo to start building dashboards.