Power Query is the tool inside Excel (Data › Get Data) that cleans, reshapes and combines data, and remembers every step. Next month you click Refresh and the whole clean-up runs again. No formulas, no macros.

Each lesson comes with messy source files and an expected-results workbook so you can check your query.

1. 1Power Query Lesson 1: What Power Query Is and Your First QueryMeet Power Query in Excel: import a CSV with Get Data, the Power Query Editor, Applied Steps, setting data types (including dd-mm-yyyy…
2. 2Power Query Lesson 2: Cleaning Text — Trim, Case and SplitClean messy text columns in Power Query: Trim and Clean, Capitalize Each Word, Replace Values, Split Column by delimiter, and Extract text…
3. 3Power Query Lesson 3: Removing Junk Rows, Duplicates and ErrorsClean an ERP-style export: remove top rows, promote headers, fill down group labels, filter out subtotals, remove duplicates and rows with errors,…
4. 4Power Query Lesson 4: Unpivot and PivotTurn a cross-tab with months across the top into a proper data table with Unpivot Other Columns, pivot data back into columns,…
5. 5Power Query Lesson 5: Merge Queries — Lookups Without VLOOKUPBring product names and categories into an orders table with Merge Queries: matching columns, join kinds (left outer, inner, anti), expanding columns,…
6. 6Power Query Lesson 6: Append and Combine a Folder of FilesStack tables with Append Queries, then combine every file in a folder with From Folder: sample file transform, file name as a…
7. 7Power Query Lesson 7: Group BySummarise data inside Power Query with Group By: basic and advanced grouping, several aggregations (sum, count, count distinct), grouping by two columns,…
8. 8Power Query Lesson 8: Custom and Conditional Columns (a Little M)Add calculated columns in Power Query: Conditional Column for size bands, Custom Column formulas for GST and totals, Column From Examples, if-then-else…
9. 9Power Query Lesson 9: Dates, Financial Year and a Calendar TableWork with dates in Power Query: extract year, month name and week, add Indian financial year and FY quarter columns, calculate days…
10. 10Power Query Lesson 10: Project — A Monthly Refresh PipelineBuild a complete refreshable pipeline: combine monthly files from a folder, clean and type them, merge product details, add FY columns, load…

Next: the Power BI course. Related: combine files from a folder, unpivot months.