Excel UNIQUE Function
Return a de-duplicated dynamic list.
What this solves
Create a live list of materials or suppliers. This pattern is useful when the business question is clear but a generic tutorial is too abstract.
The rule
=UNIQUE(array)
=UNIQUE(A2:A500)Google Sheets: The core pattern is also usable in Google Sheets; exact function support and locale separators can differ.
Real-work checklist
- Define the business key and expected grain before writing the formula, query or markup.
- Test the pattern on a small known sample where you can verify the answer manually.
- Check missing values, duplicates and data types before trusting a large result.
- Scale to the real file or database only after the logic is proven.
Common mistake
UNIQUE normalizes repeated values only by Excel equality rules; hidden spaces can make values look identical while remaining different.