Image Quality Guidelines

Images are often the first thing people notice on a website. Before reading a headline or a paragraph, users already form an impression based on visual quality.

When images appear blurry or pixelated, the website can feel unfinished even if the content and product are excellent.

Good image quality helps with credibility, visual clarity, and user confidence. It contributes to a more professional and trustworthy appearance, creates a smoother experience for users.

This tool exists to help spot issues early before they quietly affect how a website is perceived.

• Perceived quality and trustSharp visuals communicate care and attention to detail. Blurry images can distract from your content and make the experience feel less polished.
• User experienceClear images make content easier to consume and more pleasant to interact with.
• Modern screensMost devices today use high density displays. Images that look fine on older screens can quickly appear blurry on modern phones and laptops if they are not sized correctly.
• Performance and SEOWell sized images load faster. Serving images that match screen requirements helps page speed, user engagement, and search performance.

Pixelation happens when an image is displayed larger than the file was designed for.

It is similar to taking a small photo and enlarging it. Details disappear, edges soften, and individual pixels become visible.

Example: if an image file is 500px wide but is displayed at 1000px wide, the browser has to stretch it. On modern high density screens, this stretching becomes noticeable and makes the image look blurry.

There are two key sizes to keep in mind

• Intrinsic size (image file)The actual dimensions of the image file itself. For example, 2000 by 1200 pixels.
• Displayed size (on the page)How large the image appears on the website, defined by layout and CSS. For example, the image may display at 1000 pixels wide on the page.

The key insight: When the displayed size is close to or larger than the intrinsic size, the browser stretches the image. That stretching is what causes pixelation.

Here are common mistakes related to image sizing and how to avoid them:

1. Exporting images at 1x resolution
   • What happens: Images might look fine on standard displays but appear blurry on high density screens.
   • Better approach: Export images at 2x their displayed size to ensure crisp results on all devices.
2. Upscaling small images
   • What happens: Increasing the size of a small image reduces quality and introduces visual blur.
   • Better approach: Generate images from the original source at the correct size and avoid upscaling beyond 1.5 times.
3. Not using SVG when appropriate
   • What happens: Raster images (PNG, JPG) can pixelate when scaled, and require multiple sizes for different screen densities.
   • Better approach: When possible, favor SVG format. SVG images are vector-based and scale perfectly at any size without pixelation, making them ideal for icons, logos, and simple graphics.

These guidelines cover the most common image quality issues, but they are not absolute rules.

On responsive layouts, techniques like srcset and sizes allow the browser to choose the most appropriate image based on screen size and pixel density.

In some cases, perfect sharpness is not required. Small images, decorative backgrounds, or visuals heavily affected by CSS effects may justify different trade-offs.