# Why the Duplicates Button Crawls: O(n²)

Find out why a "find duplicates" button that takes a second at 10,000 songs takes about half a minute at 50,000, spot the loop-inside-a-loop that causes it, and name its growth rate: O(n²), quadratic time.

![Cheat sheet: Why the Duplicates Button Crawls: O(n²)](https://fsdtrainingmedia.blob.core.windows.net/public/images/2026/11/8b53600e91634bfdb4ae6f97aeda8924.webp)

- Category: Data Structures
- Level: Novice
- Tags: Big-O Notation, Nested Loop (software-development), Quadratic Time, software-development
- Updated: November 3, 2026

Source: https://www.ask-codey.com/cheat-sheets/big-o-quadratic-cheat-sheet