Images are essential for a great user experience, but large, high-resolution images can slow down your website if they aren’t optimized. Since we use everything from mobile phones to desktop screens, serving the same-quality image across every device is inefficient.
In this blog post, we’ll explore how to use the srcset attribute and Cloudinary to automatically load the best-sized image for any device, improving page load speed and reducing data usage.
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Optimized performance. Serve the right image size to each device, improving page load speed and reducing bandwidth usage.
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Sharp visuals across devices. Ensure images are still of good quality on all screens.
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Adaptability and future-proofing. Automatically adjust images to look great on any screen size, now and in the future.
The srcset attribute in HTML allows you to provide multiple versions of an image for different screen sizes. The browser will pick the best option based on the user’s device.
For example, a desktop user with a large screen might get a high-resolution image, while a mobile user on a slow connection will get a smaller, lower-quality version. Cloudinary works with srcset to automatically deliver the right image size for each device.
We’ll use the srcset attribute to create responsive images and then make sure these images are well-optimized using Cloudinary.
To use srcset, we’ll need multiple image sizes. Cloudinary makes this easy with URL-based transformations.
For example, here’s how you create versions for 300px, 600px, 900px, and 1200px wide images:
<img
src="https://res.cloudinary.com/demo/image/upload/w_300/sample.jpg"
srcset="
https://res.cloudinary.com/demo/image/upload/w_300/sample.jpg 300w,
https://res.cloudinary.com/demo/image/upload/w_600/sample.jpg 600w,
https://res.cloudinary.com/demo/image/upload/w_900/sample.jpg 900w,
https://res.cloudinary.com/demo/image/upload/w_1200/sample.jpg 1200w
"
sizes="(max-width: 600px) 300px,
(max-width: 900px) 600px,
(max-width: 1200px) 900px,
1200px"
alt="Sample Image">
Code language: HTML, XML (xml)The srcset attribute lists the image variants and their corresponding widths (e.g., 300w, 600w) and lets the browser choose the best image based on the device’s screen size and resolution. The sizes attribute tells the browser how wide the image should be at different screen sizes.
For example, it might pick the 300w image on smaller screens, while on larger screens, it could choose the 1200w image.
With this approach, we’ve addressed responsiveness by serving different image sizes for different devices. We must also ensure the images are compressed and delivered in the best format for each device. This is where Cloudinary steps in.
While srcset handles serving the correct image size for different devices, Cloudinary optimizes the image’s quality and format. Let’s see how this works.
Beyond just resizing, Cloudinary allows us to automatically adjust image quality and format using q_auto and f_auto. These options ensure the image is the right size and optimized for the best quality and performance, no matter the device or network.
<img src="https://res.cloudinary.com/demo/image/upload/f_auto,q_auto,w_300/sample.jpg" alt="Optimized Image">
Code language: HTML, XML (xml)When we add q_auto and f_auto to the image URL, Cloudinary’s smart algorithm automatically analyzes each image to find the best balance between quality and file size. It adjusts compression and encoding settings based on the image content and the user’s browser, ensuring the image looks good while keeping the file size small. This process helps reduce file size without noticeable loss in visual quality.
By using srcset and Cloudinary, you get:
- Faster load times. The browser selects the best image size, so smaller devices don’t download huge images.
- Reduced bandwidth usage. Users on mobile devices or slow networks won’t waste data on large images.
- Crisp visuals. Your images will look great regardless of the device you’re browsing on.
- Easy management. Cloudinary handles image transformations for all screen sizes.
Whether you’re building a personal blog or a large-scale app, using srcset and Cloudinary makes image optimization easy. Your images will load quickly, look great, and use less data, improving both performance and the user experience. With Cloudinary’s automated visual media optimization, you don’t have to worry about managing different image sizes or losing quality. Sign up for a free account today.
If you found this blog post helpful and want to discuss it in more detail, head over to the Cloudinary Community forum and its associated Discord.
