JavaScript and CSS are two vital tools we use when developing websites. Which of the two languages is better? As much as we will compare JavaScript vs. CSS, the two don’t compete, but rather complement each other in web development. They both help modify HTML pages — JavaScript modifies the behaviors of the different elements in the web, while CSS focuses on the appearance, layout, and formatting.
Let us look at the significant differences between the two languages and hopefully get you out of the JavaScript vs. CSS crossroads.
JavaScript vs. CSS: Side-By-Side Comparison
JavaScript | CSS | |
---|---|---|
Uses | Assigning specific tools to elements of a webpage hence determining their behavior. | Modifying the layout, format, and final outlook of a webpage. |
Learning Ease | Hard to learn | Moderately challenging to learn |
Programming Languages They Modify | Java, PHP | XHTML, XUL, SVG, plain XML |
Browser Compatibility | Major browsers | All browsers |
Add-Ons and Libraries Supported | jQuery, React.js, D3.js, Algolia Places, Anime.js, Underscore.js, Lodash | Tailwind, Foundation, CSS Wand, Bootstrap |
File Name Extensions | .js and .mjs | .css |
Client-Side vs. Server-Side Applications | Both client-side and server-side | Client-side only |
Resilience to Error Codes | Low | High |
JavaScript vs. CSS: What’s the Difference?
JavaScript and CSS, being programming languages, differ in many ways. Below, we will take a closer look at their key differences.
What Is JavaScript?
JavaScript is a lightweight multi-platform programming language mostly known for website development. Aside from web pages, JavaScript can be used for other non-browser applications. The scripting languages allow you to work on both the client and server side of your development, availing you of a standard library of objects.
It modifies the client side for Internet browsers and works on the server side in databases, servers, and non-browser applications. JavaScript has an API that modifies several items from date, math, and array objects, together with essential programming elements like statements, operators, and control structures.
What Is CSS?
Cascading Style Sheet, CSS, is a language that helps modify the final appearance, formatting, and layout of a website created using HTML. CSS helps make the webpage look better and ultimately impress its users. While HTML deals with the structural elements of a web page, CSS deals with the final design hues and textual styles to be incorporated.
CSS not only modifies HTML, but it also works with other programming languages. Some markup dialects that utilize CSS include XHTML, XUL, SVG, and plain XML. This wide usage shows how beneficial CSS is, from excellent device compatibility, easy upkeep, superior styling capabilities with HTML, and quick page stacking.

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Use Cases
JavaScript and CSS have different uses. CSS primarily focuses on the visual side of a webpage. The language deals with aesthetics and presentation, thus making a page much more readable and enticing to the users.
CSS allows you to change the colors of texts on a web page simply by adding a “style” code to your page’s HTML code. The language also allows you to change the layout and formatting of your page, from fonts to spacing, and image shadows.
On the other hand, JavaScript allows you to alter how different elements of your web page behave by adding valuable tools to the page. This programming language helps make an HTML or CSS element more interactive by giving it functionality.
JavaScript has many tools you can choose depending on your specific webpage needs. Using this programming language, you can easily add a calculator and keyboard shortcuts or even play exciting animations on your page during scrolling. JavaScript is very beneficial because it is highly flexible.
Ease of Learning
If you are a programming novice, which of the two languages is easier to learn? JavaScript and CSS are complex programming languages; thus, we cannot say either is easy. If you are a web developer, you must be conversant with HTML, CSS, JavaScript, and other languages.
To learn CSS, you must first have basic HTML knowledge since the two languages need each other. CSS is responsible for the outlook of HTML, and without HTML, you cannot use CSS. HTML, on the other hand, needs CSS for aesthetics. Learning CSS might take a while since the language is complex, and it brings a lot of options and factors into use. CSS has a lot of applications, and understanding all of them well will take you months.
JavaScript, a complete programming language, follows all programming logic, unlike CSS, and is thus more complex when it comes to learning. While CSS errors are manageable, JavaScript errors are troublesome, and it would take a long time to grasp the language well and do error-free work. CSS is thus more straightforward to learn than JavaScript, even if both languages are complex.
What Programming Languages Are They Applied On?
JavaScript and CSS can work hand in hand with several programming languages. We use JavaScript to modify the actions of different elements of web pages. The language primarily modifies HTML, but it can also work with other languages, including Java, PHP, and Perl.
CSS is the king of versatility since it can modify several languages. With just a mention of CSS, HTML comes to mind. However, CSS can modify some languages, including XHTML, XUL, SVG, and plain XML. CSS’s great versatility makes the language highly loved among programming experts.
Browser Compatibility
Regarding browser compatibility, CSS is better than JavaScript. You are more likely to encounter compatibility issues with JavaScript since there are different versions, and each version is supported by its browser. The language mainly works on all of the modern major browsers. However, some browsers or users disable JavaScript support which ultimately renders the language unsupported on the browser.
On the other hand, CSS is compatible with all browsers, from Chrome, Edge, Opera, Safari, and Firefox, which means that you can freely use CSS regardless of your browser. And just like that, CSS wins this browser compatibility test.
Add-Ons and Libraries Supported
JavaScript and CSS support different add-ons and libraries. Add-ons are software components that provide specific functionalities and features to an existing programming language.
JavaScript has a variety of useful libraries. The libraries are meant for different users since they have different uses. These libraries include;
- jQuery
- React.js
- D3.js
- Underscore.js
- Lodash
- Algolia Places
- Anime.js
CSS also has a great line-up of add-ons to ensure your projects are well-refined and pleasing. These add-ons include Tailwind, Foundation, CSS Wand, and Bootstrap.
Client-Side vs. Server-Side Applications
CSS, being a style markup, exclusively works on the client side. The language helps modify the final outlook of the webpage. After developing your web page using HTML, you can now adjust the structure, fonts, colors, and general aesthetics of your page using this language.
JavaScript can be used for both client-side and server-side applications. In websites, Javascript is a client-side language, and after some internal compilation, the language reads the scripts before executing the instructions on the client’s side. However, JavaScript is not secure when run on the user’s machine, and you should always avoid processing passwords and sensitive information using the language.
JavaScript can also work on the server side in the case of databases, browsers, and non-server applications. This means that JavaScript can serve both functions depending on your programming needs, thus winning this client-side vs server-side application comparison.
File Name Extensions
In programming, file name extensions are the identifiers found at the end of file names. These identifiers come after a period; they tell the computer what type of file it is dealing with, its characteristics, and its use. CSS uses “.css” as its file name extension, whereas JavaScript uses both “.js” and “.mjs.”
Resilience
CSS and JavaScript react differently to errors. Even if you break a single CSS rule, your whole web page will not be significantly impacted when using CSS. However, you might mess with your layout if you miss a tag. Despite the nature of the errors, your page will still load unless it is an extreme case.
On the other hand, a single JavaScript syntax error will break your whole page. No matter how small the error is, you must find and fix it before your page can resume working. In this process, you may lose some of your work and end up redoing already-done work. It goes without saying that CSS is more resilient than JavaScript. When dealing with JavaScript, you must always ensure your work is error-free to avoid inconveniences.
Optimization
Optimization is a vital strategy in programming since it allows the developer to modify a code or language to improve certain aspects, including speeds, memory utilization, and CPU time. JavaScript fails in this sector since it lacks API access out of the box.
In contrast, CSS has a broader optimization scope. The declarative language allows the browser to accelerate its hardware, thus making CSS faster. You can optimize your CSS in many ways; eliminate unnecessary styles, minify, cache, or compress the CSS. Additionally, you can split the CSS not required into several files and effectively reduce CSS render blocking.
CSS has better optimization than JavaScript. If optimized well, the language can offer its users impeccable performance.

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JavaScript vs. CSS: Pros and Cons
JavaScript Pros | JavaScript Cons |
---|---|
Versatile programming language | Can be vulnerable to security risks if not coded properly |
Enables interactivity and dynamic user interfaces | Can slow down page loading times if not optimized correctly |
Runs directly in the browser, improving application performance | Browser compatibility issues may arise |
Large and active developer community | Lack of strong typing can lead to errors in code |
Compatible with a wide range of web browsers and platforms | Limited access to system resources outside the browser |
CSS Pros | CSS Cons |
---|---|
Can significantly improve the visual appearance of web pages and user interfaces | Can be complex and difficult to learn for beginners |
Allows for the creation of responsive and adaptable web designs that can adapt to different devices and screen sizes | Cross-browser compatibility issues may arise |
Enables efficient and organized style management for larger web projects | Can be time-consuming to create and implement complex designs |
Allows for easier maintenance and updates to web designs | Limited support for dynamic and interactive elements without JavaScript |
A large community of developers and resources available for support and learning | May not be suitable for all web development use cases, such as server-side programming |
JavaScript vs. CSS: 7 Must-Know Facts
Having already covered how JavaScript and CSS differ, here are some must-know facts about the two programming languages.
- CSS is used on the visual side of webpages to improve aesthetics, the layout, and other visible components. JavaScript focuses on how the different elements of your web page behave by adding valuable tools to the page.
- Regarding learning, both languages are complex, and it would take a long time to understand them fully. However, JavaScript uses basic programming logic, and its errors are harder to manage than CSS, and it is thus more complex and harder to learn.
- CSS is compatible with all browsers, whereas JavaScript encounters compatibility issues and only works on major browsers. The compatibility issue arises because each JavaScript version is compatible with its browser.
- JavaScript and CSS are constantly evolving to keep pace with the latest trends and technologies in web development. For example, recent updates to CSS include support for variables, grid layouts, and animations, while JavaScript has seen the development of new libraries and frameworks like React and Vue.js that make it easier to build complex web applications.
- CSS uses “.css” as its file name extension, whereas JavaScript uses both “.js” and “.mjs.”
- CSS is more resilient than JavaScript since a single CSS error does not affect the webpage much. However, when using JavaScript, any syntax error has to be fixed, or the page will not run. These errors can also make you lose some work.
- CSS has a broader optimization scope allowing users to improve certain aspects of the code for convenience. JavaScript does not allow optimization since it lacks API access out of the box.
JavaScript vs. CSS: Which Is Better? Which One Should You Use?
Between JavaScript and CSS, which is better? JavaScript is more advanced than CSS when it comes to web planning. JavaScript offers many functionalities, from creating liveliness to adding specific tools and page elements. Compared to CSS, JavaScript is better since CSS users are confined to developing the website’s plan, aesthetics, hues, tables, and boxes, among others.
JavaScript thus wins this comparison owing to its versatility in use cases. However, CSS is still a strong opponent since it is an essential website development language. Its advantages include superb browser compatibility, better optimization, remarkable resilience, and ease of learning.
So which one should you use? Your ideal language depends on your specific needs. If you require a programming language that can improve the general outlook of your already-developed website, CSS will suit you best. However, if you want to incorporate certain functionalities into the elements of your website, JavaScript will sort you out.
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