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Seyed Ahmad
Seyed Ahmad

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use of the Image component in Next.js versus using regular `<img>` tags

Using the Image Component in Next.js:

  1. Automatic Optimization: Next.js automatically optimizes images, which includes resizing, compressing, and converting to modern formats like WebP.

Example:

   import Image from 'next/image'

   function MyComponent() {
     return (
       <Image
         src="/large-image.jpg"
         width={500}
         height={300}
         alt="A large image"
       />
     )
   }
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In this case, Next.js will automatically serve an optimized version of large-image.jpg, potentially reducing its file size significantly without sacrificing quality.

  1. Lazy Loading: Images are loaded only when they approach the viewport, improving page performance.

Example:

   <Image
     src="/heavy-image.png"
     width={1200}
     height={700}
     alt="A heavy image"
     loading="lazy"
   />
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This image won't load until the user scrolls near it, saving bandwidth and improving initial page load time.

  1. Preventing Cumulative Layout Shift (CLS): It reserves space for images before they load, preventing layout shifts.

Example:

   <div style={{ position: 'relative', width: '100%', height: '300px' }}>
     <Image
       src="/banner.jpg"
       layout="fill"
       objectFit="cover"
       alt="Banner image"
     />
   </div>
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This ensures the space for the banner is reserved, preventing content below from jumping when the image loads.

  1. Responsive Images: Easily optimize images for different devices.

Example:

   <Image
     src="/responsive-image.jpg"
     sizes="(max-width: 768px) 100vw, (max-width: 1200px) 50vw, 33vw"
     fill
     alt="Responsive image"
   />
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This image will adapt its size based on the viewport width, ensuring optimal display across devices.

  1. Improved Core Web Vitals: By optimizing images, it helps improve Core Web Vitals metrics.

However, using regular <img> tags instead of the Image component is also possible:

  1. Simplicity: For small projects, using <img> tags might be simpler.

Example:

   <img src="/simple-image.jpg" alt="A simple image" width="200" height="150" />
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  1. More Control: If you need precise control over how images are loaded, you might prefer custom solutions.

Example:

   <img 
     src="/custom-image.jpg" 
     alt="Custom loaded image"
     loading="lazy"
     decoding="async"
     onload="this.classList.add('loaded')"
   />
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This gives you more control over the loading process and allows for custom behaviors.

  1. Compatibility with Legacy Code: When migrating an old project, changing all <img> tags to Image components might be time-consuming.

Example of legacy code:

   <div class="legacy-image-container">
     <img src="/old-image.gif" alt="Legacy image" />
   </div>
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In this case, keeping the original <img> tag might be easier for maintenance.

  1. No Need for Optimization: If your images are already optimized, using <img> tags might be sufficient.

Example:

   <img 
     src="/pre-optimized-image.webp" 
     alt="Pre-optimized image"
     width="800"
     height="600"
   />
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If you've already converted your image to WebP and optimized its size, the benefits of the Next.js Image component might be less significant.

The decision ultimately depends on your project's specific needs. If performance and optimization are high priorities, using the Image component is recommended. But if simplicity or compatibility with existing code is more important, using regular <img> tags is also acceptable.

Remember, you can mix and match in your project. Use the Image component for critical, above-the-fold images that need optimization, and regular <img> tags for less important or already optimized images.

Top comments (1)

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seyed_ahmadgholami_36bc9 profile image
Seyed ahmad Gholami

I don't know that about Image component