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Master CSS breakpoints for responsive design and enhance user experiences. Learn effective techniques to optimize your website's responsiveness.
Nimritee
January 12, 2026
Today’s potential customers are smart, sophisticated, and time-starved and they want their requirements to be addressed instantly. Therefore, an ultimate user experience is crucial to the success and survival of organizations that aim to enhance their user’s engagement. The goal would be to convert these visitors into customers which would eventually add to the revenue of the organization.
A website (or app) that adheres to the fundamentals of responsive web design offers an amazing experience across various device viewports (or screen sizes) is part of the ideal online user journey. A responsive site design should prioritize easy navigation, dynamic and legible information, and other elements. A smooth user experience across various device viewport widths may be difficult given the wide variety of devices on the market. In order to implement responsive design for websites (and web applications), CSS responsive breakpoints can be crucial.
CSS responsive breakpoints are quite useful for creating a responsive web design, as it offers an awesome user experience on different screen sizes. This is realized by splitting the design into a smaller version(s) of the website based on the device’s screen size.

In this blog, we deep dive into breakpoints CSS and how it can be used to build responsive designs. The end result – website (or web app) with a top-notch user experience across different device viewports.
Let’s get started!
New to CSS Selectors? Check out this Ultimate CSS Selector cheat sheet to boost your web designing career.
CSS breakpoints are the points added in the code, the website content responds to these points depending on the device screen size. This helps in displaying an ideal layout to the end-user. CSS responsive breakpoints are used along with media query due to which it is also known as CSS media query breakpoints.
In other terms, best CSS media query breakpoints are the pixel values that a developer can specify in the breakpoints CSS code. An adjustment is made to give a pleasant user experience when a responsive website encounters such pixel values.
Read: How To Use CSS Media Queries For Responsive Design?
Let’s view the TestMu AI website on different device viewports to understand the basic essentials of CSS responsive breakpoints.
Desktop View
When we view the website on a simple desktop screen, the entire navigation menu is visible at the top of the page.

Mobile View
When the same website is viewed on a mobile device, the navigation bar appears like a hamburger menu on the top right corner of the screen. This is because the website is viewed on a device with a smaller display size.

It’s important to develop a mobile website that functions seamlessly across all devices, screen sizes, and resolutions. However, developers must bear in mind that 55% of all web traffic came through mobile phones. Therefore, after incorporating CSS responsive breakpoints in your websites, you need to test mobile view of website to ensure that your websites are well-optimized to run on different mobile device viewports.
Read More: How To Get Started With Mobile Website Testing In 2021?
Read More: How To Get Started With Mobile Website Testing In 2021?
LT Browser – a mobile friendly checker tool that allows you to test mobile view of website across multiple device viewports, including mobiles, tablets, desktops, and laptops. LT Browser comes with numerous features for developers to perform mobile testing and make their entire web dev process even smoother.

Some of the amazing features that LT Browser offers are:
To delve deeper into the features of LT Browser, read our blog on the best features of LT Browser – a browser for developers!
You can also go through our LT Browser tutorial to easily kick start your mobile web testing.
The most challenging part is to select the best media query CSS breakpoints. There are no standard rules or syntax since different frameworks use different breakpoints.
Here are the two approaches to apply breakpoints CSS:
Media query CSS breakpoints can be selected based on the device on which the website is being rendered. However, this is not a preferred approach since new devices are released frequently, and keeping up with new ones requires substantial effort.
Moreover, when a new device launches in the market, developers need to add a new breakpoint to the newly launched screen resolution. Applying the same breakpoint repeatedly to every device can turn out to be a cumbersome activity.

Depending on your website’s intent and the target audience, you can cover at least all the popular devices and subsequently apply breakpoints to them. As per a survey, close to 50 percent of web traffic originates from mobile devices. Therefore mobile first web design has become an absolute necessity in today’s time where mobile devices have become an indispensable part of our lives!
Read: Why Is Responsive Web Design Important?
Read: Why Is Responsive Web Design Important?
With this Responsive testing tutorial for beginners, you will learn how to perform Responsive Testing of your website on the TestMu AI platform.
Here are examples of a few device-specific CSS media query breakpoints.

For iPhone 12 Mini
/* ----------- iPhone 12 Mini ----------- */
/* 2340x1080 pixels at 476ppi */
@media only screen
and (device-width: 360px)
and (device-height: 780px)
and (-webkit-device-pixel-ratio: 3) { }
For iPhone 12, 12 Pro
/* ----------- iPhone 12, 12 Pro ----------- */
/* 2532x1170 pixels at 460ppi */
@media only screen
and (device-width: 390px)
and (device-height: 844px)
and (-webkit-device-pixel-ratio: 3) { }
For iPhone 11
/* ----------- iPhone 11 ----------- */
/* 1792x828px at 326ppi */
@media only screen
and (device-width: 414px)
and (device-height: 896px)
and (-webkit-device-pixel-ratio: 2) { }
For OnePlus 6
/* ----------- OnePlus 6 ----------- */
@media only screen
and (min-width: 412px)
and (max-width: 869px) {}
You can also set the breakpoints for common device groups instead of specific devices.
/* For extremely small screen devices (595px and below) */
@media only screen and (max-width: 595px) {...}
/* Small screen devices (600px and above) */
@media only screen and (min-width: 600px) {...}
/* Medium screen devices (768px and above) */
@media only screen and (min-width: 768px) {...}
/* Big screen devices (889px and above) */
@media only screen and (min-width: 889px) {...}
/* Extra big screen devices (1200px and above) */
@media only screen and (min-width: 1200px) {...}
Instead of using device-based breakpoints, it’s better to use the website content for covering more scenarios in order to apply CSS media query breakpoints. In this approach, we simply set a breakpoint at each point where the content layout is misaligned. This method greatly simplifies the implementation along with easing the management of media queries.
As shown in the below example, on minimizing the screen size; the content begins to distort which in turn hampers the readability. To avoid this scenario, we insert CSS media query breakpoints to improve the readability aspects of the content.

Here are the content-based breakpoints for different screen sizes.
For Resolutions 768px And Above
@media only screen (min-width: 768px){
...
}
For Resolutions Between 768px And 960px
Note: We can also set a range with breakpoints, hence the CSS will only be applied to those specific ranges.
@media only screen and (min-width: 845px) and (max-width: 911px){
...
}
You can add breakpoints CSS using min-width, max-width, or even a combination of both. When designing the layout with a mobile-first approach in mind, it is recommended to use min-width breakpoints. By default, we would be setting the styles for small screen devices and later add & adjust for bigger screens.
Likewise, if we are designing our layout for large-screen devices, we should use max-width breakpoints. By default, we would be setting the styles for big-screen devices and later add & adjust for smaller screens.
When defining things such as margins, padding, and font sizes, we mostly use pixels, but they are absolute units which means that they are not affected by any other factor in breakpoints CSS.
In comparison, the relative units ems and percentages get their final size based on multiple factors like the parent element’s font size or the root font size in the browser. As a result, using ems or percentages will significantly reduce the need for media-query-specific classes and make the website more responsive and easier to manage.
We need not create multiple CSS media query breakpoints for every device width. This approach was used earlier for creating a responsive website when there were fewer devices in the market.
You can make the process of building a website much easier if you know which CSS media breakpoints to use. Several CSS media breakpoints will likely work for most websites, including popular devices and content types.
Here are the most popular frameworks – Foundation, Bootstrap, and Bulma.
The most common screen resolution in 2022, as per the Worldwide Screen Resolution Stats from Sept 2021 to Sept 2022, is 1920×1080, accounting for 9.94% of devices. The second most common resolution is 1366×768, making up 6.22% of devices.
Mobile-first design is currently considered the industry standard and is widely used by brands that want to be on the cutting edge of responsive website design. Therefore, employing these breakpoints will result in higher degrees of responsiveness for websites.
With many devices rolling out, it’s impractical to cover all the new devices for applying CSS responsive breakpoints. Rather, try to choose breakpoints based on the web design and target devices that are extensively used by the audience in the target markets.
Some common Breakpoints For Responsive Design are:
Using the CSS breakpoints mentioned above, you can create a simplified and manageable responsive website.
Also Read: The Ultimate Guide To Building A Mobile Friendly Website
Also Read: The Ultimate Guide To Building A Mobile Friendly Website
For example, consider the TestMu AI website; the automation testing page has two content boxes aligned horizontally when viewed on a desktop. The same is piled to one column on mobile and tablet devices.

Mobile design with one column
Mobile design with one column
Beginning with mobile widths and scaling up, selecting the viewport width at which we want the design to change to two columns. So, how do you test the responsiveness of your website on different devices and viewports? This is where LT Browser – a free-to-use mobile-friendly test tool for responsive test, can be leveraged for ensuring that your website (or web app) scores well on all the aspects related to website’s responsiveness.

Desktop design with two columns
Desktop design with two columns
We can start with 3 to 4 breakpoints covering all screen sizes; from small screens to big screens; and set the breakpoints at 42em, 60em, and 81em. The mobile phones will fall under the 768px category, and tablets will approximately fall above 768px. So basically, all the small screen devices mostly fall between 480px to 1024px whereas the large screen devices will fall above 1201px.
This method lets you incorporate all devices within these ranges of viewport widths.

Operating with a small range of breakpoints will help us maintain the responsiveness of the styles in a consistent manner.
Adding correct CSS responsive breakpoints takes immense time and effort. Therefore after implementing CSS media query breakpoints, it is essential to perform responsive testing websites to check how your website looks and behaves across various screen sizes. In addition, you can keep a web design checklist in hand while developing websites with CSS breakpoints.

In this post, we have learned how to use CSS breakpoints for responsive design to help developers reduce their pain points while debugging a website. Along with responsive testing, you can also leverage TestMu AI – a cross browser testing platform to test the browser compatibility of websites with CSS breakpoints across 3000+ real browsers and operating systems online.
If you’ve your own experience with CSS breakpoints, please share them in the comment section below.
Happy Designing!
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