Local Storage in JavaScript
localStorage lets you save data in the user's browser – even after closing the tab or restarting the computer. It's simple, synchronous, and great for small amounts of data like settings or progress.
Data is stored as strings and tied to the domain. Each site gets about 5-10 MB of space.
Saving Data with setItem
Retrieving Data with getItem
Storing Objects (JSON.stringify/parse)
localStorage only stores strings – use JSON to save objects or arrays.
Removing and Clearing
Practical Example: Theme Switcher
Limitations
- Only strings (use JSON for objects)
- About 5-10 MB limit per domain
- Synchronous (can block if overused)
- Same-origin policy – no cross-domain access
Quick Quiz
We have reviewed and checked the materials, but errors may still occur. The content is provided for educational purposes only, so use it at your own responsibility and verify with other sources if needed.
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