2021-02-18
1598
#react
Adebola Adeniran
34347
Feb 18, 2021 â‹… 5 min read

React.memo vs. useMemo: Major differences and use cases

Adebola Adeniran Hi! I'm Adebola! I'm a full-stack React/Node.js and Ruby on Rails engineer from Nigeria. I mentor junior developers via the Google Developer Program, and I'm a regular contributor to some of the most widely read programming blogs. You can follow me on Twitter @debosthefirst.

Recent posts:

Fix over-caching with dynamic IO caching in Next.js 15

Next.js 15 caching overhaul: Fix overcaching with Dynamic IO and the use cache directive.

David Omotayo
Aug 6, 2025 â‹… 10 min read
LLMs are facing a QA crisis here’s how we could solve it

LLMs are facing a QA crisis: Here’s how we could solve it

LLM QA isn’t just a tooling gap — it’s a fundamental shift in how we think about software reliability.

Rosario De Chiara
Aug 4, 2025 â‹… 7 min read

Windsurf vs. Cursor: When to choose the challenger

Windsurf AI brings agentic coding and terminal control right into your IDE. We compare it to Cursor, explore its features, and build a real frontend project.

Chizaram Ken
Jul 31, 2025 â‹… 9 min read

The CSS if() function: Conditional styling will never be the same

The CSS Working Group has approved the if() function for development, a feature that promises to bring true conditional styling directly to our stylesheets.

Ikeh Akinyemi
Jul 30, 2025 â‹… 12 min read
View all posts

2 Replies to "<code>React.memo</code> vs. <code>useMemo</code>: Major differences and use cases"

  1. Nice easy to read article. But I think you should make it clear that React.memo and useMemo are completely different: the functional component is always being rerendered, which is rexecuted with the same props, as can be seen from react tools/highlight rerenders (even though with no dom changes to perform to perform in this particular case).

  2. In your useMemo use case, does it mean no re-rendering if UseMemoCounts component shows the same times when clicking cheese buttons? ParentComponent sends the same value as a prop to UseMemoCounts. It just shows the same number and it keeps re-rendering, doesn’t it?

Leave a Reply