Image resizing refers to changing the dimensions of a digital image. This can be done by either increasing or decreasing the number of pixels in the image, which in turn affects the overall size of the image. Image resizing is commonly used to adjust the size of a photo so that it can be shared on social media, printed, or used in different forms such as websites, presentations, and documents.

There are two types of image resizing:

  1. Resampling: This method involves adding or removing pixels from the image to change its size. This can result in a loss of quality, particularly when the image is enlarged.
  2. Changing the image resolution: This method involves changing the number of pixels per inch in the image without adding or removing any pixels. This method can be used to change the size of an image without losing quality, but it will change the size of the image in inches or centimeters.

It is important to note that, regardless of the method used, resizing an image will always result in some loss of quality, especially if the image is enlarged significantly.

Why do you resize images for the web?

Resizing images is essential for several reasons when they are used on the internet.

Firstly, it can significantly reduce the image's file size, leading to faster loading times on websites. This is especially important for users with slower internet connections or mobile devices, as larger images can take longer to load and use more data.

Secondly, it allows the image to be displayed at the appropriate size on different devices. Without resizing, an image may appear too large or too small on different screens, which can negatively impact the user experience.

Thirdly, it can reduce the storage space images take on your server.

Finally, it can also help to optimize the images for search engine optimization (SEO) by reducing the size of the images, you can improve the performance of your website and make it more likely to appear at the top of search engine results.

How much does resizing, in general, reduce image size?

The amount that resizing an image can reduce its file size depends on several factors, such as the original resolution of the image, the file format, and the specific resizing method used.

In general, reducing an image's resolution (number of pixels) can significantly impact its file size. For example, reducing the resolution of an image from 4000x3000 pixels to 800x600 pixels can result in a file size reduction of 75% or more.

Compression can also be applied after resizing, which could give an additional size reduction. The file format also plays a role in the final size of the image, with lossless formats like PNG generally resulting in larger file sizes than lossy formats like JPEG.

As a general rule of thumb, resizing an image can reduce its file size by a significant amount, with the exact amount depending on the original resolution, file format, and specific resizing method used.

Most popular software to use for resizing images

Many software can be used to resize photos, but some of the most popular ones are listed below.

  • Adobe Photoshop
  • GIMP
  • PaintShop Pro
  • IrfanView
  • FastStone Image Viewer
  • XnView MP
  • Corel PaintShop Pro
  • ACDSee Photo Studio
  • Adobe Lightroom
  • Photoscape

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