How To Resize An Image On A Mac Or PC

Ever tried to upload a photo to your website, only to get the dreaded “File too large” error? We’ve all been there, but there’s an easy fix. It’s called resizing.

Resizing an image on your Mac or Windows machine can mean two things: changing file size, or changing image size.

And guess what? You don’t need a degree in digital wizardry to adjust the resolution or tweak the pixel count. Whatever it is you need to do, it’s simply a matter of choosing the right software for the job.

Today we’re spilling the beans on everything you need to know to resize an image properly. The processes you’ll learn about in this article work on both Windows and Mac devices. Read on to learn how to get any image down to the perfect size, so you can keep your website loading lightning fast.

What Is The Difference Between File Size And Image Size?

Think of the file size as the weight of your image. For photos, it’s usually measured in kilobytes (KB) or megabytes (MB). Typically, the larger an image, the larger its file size, and the more space it takes on your computer’s hard drive.

Image size, on the other hand, has nothing to do with the amount of space a file takes up on your device. It refers to the dimensions of your photo—how wide and tall it is. Both image width and image height are measured in pixels. Think of it as the size of your digital canvas.

In a nutshell, file size is how heavy your image is, and image size is how big it looks on a screen.

Knowing the difference helps you choose the right format and size for various platforms, which have different requirements for both image sizes and file sizes.

Why Should Website Images Be Resized And Optimized?

Using big, bulky images that haven’t been resized or optimized on your website often leads to slow loading times and sluggish performance. Resizing and optimizing your website images can seriously enhance the user experience by keeping your website fast.

But that’s not the only reason you should be optimizing images before you use them in landing pages or blog posts. It’s also important for SEO. Here’s why:

  • Faster Page Loading Times: Search engines prefer websites that load quickly. Large, unoptimized images can slow down your site and hurt your SEO ranking.
  • Improved User Experience: Users leave when a site takes too long to load. Optimizing images makes it easier for visitors to use your website. This leads to lower bounce rates, which means users spend more time browsing content on your website. Google and other search engines see this increased engagement as a positive signal that helps you rank higher in organic search.
  • Better Image Search Ranking: Properly optimized images that have a file name, alt text, and proper sizing are more likely to appear in image search results, and can help drive additional traffic to your site.
  • Mobile Optimization: With the use of mobile devices continuously on the rise, optimizing image file sizes keeps your website performing well on all devices, which is another key factor in Google’s ranking algorithm.

Image optimization isn’t just about getting your files to the smallest possible size without sacrificing their quality. It’s a necessary practice that helps you maintain fast loading times while keeping your site phone-friendly and accessible for users and search engines.

How Do You Know If An Image Is Too Large To Use On A Website?

Ideally, your images should be lean (under 1MB) to make sure your site loads quickly and without issues. If you upload lots of images larger than 1MB, you risk slowing down your site.

Before uploading a new photo, a good practice is to inspect the file size first.

On your computer, right-click the image file and choose ‘Properties’ on Windows or ‘Get Info’ on a Mac to see the size. If it exceeds 1MB, it’s probably too bulky for efficient web use.

If you do find an image with a file size that’s too large, it’s often still usable. You’ll just need to use Adobe Photoshop or an online application to reduce the file size to less than 1 MB.

How Do You Choose The Right Image Resolution And Size?

For websites, consider the layout and design. How do you plan to use the images? Large banner images need higher resolution to remain clear on different screen sizes, but keeping the file size down is just as important to avoid slow loading times.

Aim for a balance where the image retains good quality without being too heavy. A resolution of 1920 pixels wide is usually plenty for full-width images on standard web pages.

If you’re optimizing an image for social media platforms, they usually specify optimal resolutions and sizes for profile pictures, posts, and cover photos.

For instance, a Facebook cover photo has different dimensions and resolution requirements than an Instagram story image. Sticking to the particular specifications on each platform keeps all images looking sharp and loading quickly.

Here are the recommended image sizes for standard photo posts on popular social media platforms:

  • Facebook: 1200 x 630 pixels
  • X (Twitter): 1600 x 900 pixels
  • LinkedIn: 1200 x 627 pixels
  • Instagram:
    • 1080 x 1080 pixels for square posts
    • 1080 x 608 pixels for landscape photos
    • 1080 x 1920 for story posts

For mobile apps, consider the average cell phone’s screen size and resolution. Images need to be high enough in resolution to look good on high-definition screens, but optimized to avoid excessive memory usage, which can negatively impact performance.

What Are The Different Ways To Resize An Image?

Depending on your needs and available tools, you have a few routes to consider.

First up, you can use Adobe Photoshop, the heavyweight champ of image editing. Launch Photoshop, and you’ve got a powerhouse of resizing tools at your fingertips. You can adjust image dimensions, file size, and quality with precision. It’s ideal for those who need detailed control over their images.

But what if you don’t have Photoshop?

No worries. If you host your website on WordPress, you can also use plugins to resize an image.

If you’re hosting your site on another platform, AI software for resizing images is extremely easy to find and use, and many are available for free. These online tools use smart algorithms to adjust your image size without losing quality. Just upload your photo, select your desired size, and let the AI work its magic.

Whether you choose to pay for Adobe Photoshop, use WordPress plugins, or opt for the convenience of an online image upscaler, each method can get the job done.

Here’s how to resize an image using either Photoshop or online tools.

Resizing Images In Photoshop

Photoshop is ClearBrand’s preferred method for resizing images. This is because Photoshop gives you a level of granular control over both file size and image quality that you won’t often find included with online tools – especially the free ones.

To resize an image, start by opening your file in Photoshop.

Then, navigate to the ‘File’ menu and select ‘Save for Web’. This option is specifically designed to help you optimize images for online use.

You’ll be taken to a settings panel where you can adjust image resolution, dimensions, and choose a format (PNG, JPG, or WEBP) for each image.

With larger files, you’ll want to first adjust the size of the actual image by tweaking the height and width. Then fine-tune the quality. Going about it like this helps you reduce file size without sacrificing more quality than necessary.

As you adjust the image size, remember that a width larger than 1920 pixels is often unnecessary for web use. With this in mind, you’ll want to pay special attention to the dimensions on stock images, since since large ones can stretch up to 7000 pixels or more in width.

After you’ve played with the image size, move on to adjusting the image quality. When adjusting quality settings, never drop below 70%. If you do, images won’t be of high enough quality for use on your website.

The ‘Save for Web’ feature also has presets that can be incredibly handy here. The presets help you balance file size and quality efficiently without worrying about the exact dimensions of your images.

A woman resizes images in Photoshop while working in a shared office

Resizing Images With WordPress Plugins

You can use WordPress plugins like ShortPixel and Imagify to do all of the optimization work within your website. These plugins can process multiple images simultaneously, and keep them perfectly optimized for web performance by adjusting photo resolution and fixing low-resolution image issues.

Both of these plugins choose the best compression settings for you and convert images to efficient formats like WebP.


ShortPixel intelligently reduces file sizes without sacrificing quality for multiple images at once, so it’s an excellent choice for websites with lots of photos.

This plugin offers options for both “Lossy” and “Lossless” compression. “Lossy” images will be smaller files, but they may look grainy. “Lossless” images are larger in file size, but don’t look grainy.

It optimizes any image or PDF document on your website and uses next-gen file formats in addition to JPEG, PNG, and WEBP.


Imagify is another powerful WordPress plugin that’s great for image optimization. It’s features are extremely similar to ShortPixel’s.

Imagify also allows you to optimize multiple images at once. It supports popular formats like JPEG and PNG, plus next-gen standards like WEBP and AVIF.

On the free plan, you can optimize 20MB of images monthly—around 200 pictures. If you need more, check out their paid plans here.

Resizing Images With Other Online Tools

Online tools for resizing images offer a quick and easy solution when you don’t have access to software like Photoshop. These tools often come with helpful tips and automated features to streamline the optimization process.

Many modern image resizers are powered by AI. that automatically chooses the best settings for your image. This is known as resampling. When resampling occurs, software adjusts the number of pixels in an image to fit your desired dimensions without losing quality.

Using these tools is straightforward, and there are tons of options to choose from. At ClearBrand, we prefer to use You can also use or the Online PNG And JPEG Compression Tool from (and no, we’re not an affiliate of any of these companies – we just appreciate how easy it is to use their tools).

Regardless of which online tool you decide to use, you usually just upload your image, specify the new size, and let the tool handle the rest. They are particularly useful for quick edits or when you need to resize images on the go.

Screenshot of Website Planet’s online PNG and JPEG compression tool

Is It Possible To Resize An Image Manually?

You can manually resize an image with the help of tools like Photoshop, but there’s no easy way to do so without using software designed to edit images.

When you resize an image manually in Photoshop, you have full control over the final outcome. You can adjust the surrounding pixels and maintain the aspect ratio to ensure the image doesn’t stretch or skew unnaturally.

This isn’t always possible with free online tools, although offers the same level of control as Photoshop, minus the price of a monthly subscription.

What Format Should Be Used When Resizing Images?

Choosing the right image format requires you to consider how you plan to use the image. For use on the web, a format like JPEG, PNG, or WEBP is best in most cases.

JPEG (or JPG) is often the go-to format for its balance between quality and storage space. It’s ideal for photos where you need to manage file size without significantly sacrificing resolution.

JPEGs are perfect for web images because they can be compressed to reduce size, so they’re quick to load while maintaining a decent visual quality.

PNG is a popular format when you need to preserve details like hard edges, or if the image has transparency or no background.

PNG files handle these aspects better than JPEGs. They provide a clear, sharp image without the blur that sometimes comes with JPEG compression.

That said, PNG files are usually larger and lead to slow loading times. That’s why JPEG is the preferred image format in most cases.

WEBP is a modern format that offers the best of both worlds. It provides better compression than JPEG (resulting in smaller files), but also supports transparency like PNG.

WEBP maintains high-quality visuals even at lower file sizes, so it’s an excellent choice for web images. It’s becoming more and more popular because it optimizes loading times without compromising image integrity.

Can I Increase Image Quality And File Size For Low-Resolution Images?

Dealing with low-resolution photos can be a challenge, especially when you need them to look sharp and clear. Today, there are easy-to-use tools to enhance image quality and boost resolution.

With a bit of software, you can fix low-resolution photos that look like they were taken with a potato, and make them look professional and clean.

To fix low-resolution pictures, use either image editing software (like Photoshop) or online tools that offer features like ‘super resolution’ or ‘increase image resolution.’ Resizing tools typically offer options to adjust resolution, apply noise reduction, and choose resampling methods like bicubic sharper or smoother to fix low-resolution images.

Using these options can convert a low-resolution photo into a higher resolution one by adding more pixels and improving detail.

This process is called ‘upsampling,’ where the tool generates new pixels to fill in the gaps and make the image appear clearer and more defined.

It’s still important to note that while you can significantly improve image quality, there’s a limit to how much you can increase resolution before the image starts to look unnatural.

It might be necessary to test a few different tools until you find a balance where the photo gains clarity and detail without introducing artifacts or losing its original character. If you want to give it a try yourself, you can start by trying PixelCut.

Screenshot taken from’s image upscaler in a web browser

Get A Website With Stunning, Optimized Images From ClearBrand

Images on your website are not decorations. They’re powerful tools that attract, engage, and convert visitors into customers.

Now that you’re familiar with the ins and outs of resizing and optimizing images for any platform, you can upload fully optimized images that keep your website loading fast while looking fantastic.

Every optimized image helps your website perform better. And while the technicalities might seem daunting at first, the process is super straightforward.

At ClearBrand, we understand how well-optimized images can boost the user experience and help you rank higher in organic searches. If you’re looking to take your website to the next level with clear messaging and images that tell your brand’s story in every pixel, speak with a marketing specialist today. We’ll help you create a digital space that attracts more visitors and converts them into customers.

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