Stop Using getBoundingClientRect() in Loops. It’s Killing Your Performance.

📰 Medium · JavaScript

Learn why using getBoundingClientRect() in loops can severely impact performance and how to optimize it

intermediate Published 21 Apr 2026

Action Steps

Avoid using getBoundingClientRect() in loops to prevent layout thrashing
Use caching or memoization to store the results of getBoundingClientRect()
Consider using alternative methods such as getClientRects() or DOMRect
Optimize your code by reducing the number of DOM reads and writes
Test and profile your code to identify performance bottlenecks

Who Needs to Know This

Frontend developers and engineers can benefit from this knowledge to improve the performance of their web applications

Key Insight

💡 getBoundingClientRect() can cause layout thrashing and severely impact performance when used in loops

Key Takeaways

Learn why using getBoundingClientRect() in loops can severely impact performance and how to optimize it

Full Article

Title: Stop Using getBoundingClientRect() in Loops. It’s Killing Your Performance.

URL Source: https://medium.com/@laxmiphalak/stop-using-getboundingclientrect-in-loops-its-killing-your-performance-4610f178877f?source=rss------javascript-5

Published Time: 2026-04-21T16:07:46Z

Markdown Content:
# Stop Using getBoundingClientRect() in Loops. It’s Killing Your Performance. | by Laxmi Phalak | Apr, 2026 | Medium

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# Stop Using `getBoundingClientRect()` in Loops. It’s Killing Your Performance.

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Stop Using getBoundingClientRect() in Loops. It’s Killing Your Performance.

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