Best Free CSS Code Generator Webapps

SpriteGen, CSSmatic, Base64, CSS3 Generator, Flexy Boxes, and more.

Smart coders know how to save time and build websites fast. Many IDEs let you save snippets but few IDEs have custom code generators.

That’s where this list comes in handy with a huge collection of free CSS code generators from all over the web.

You’ll find everything from custom gradients to modern CSS animations and a whole lot more. Plus these webapps are totally free so you can bookmark your favorites to keep them handy for all your dev projects.

Flexy Boxes

The future of CSS is flexbox as it keeps gaining more attention from developers. It’s a new way of organizing page content that works quite well for responsive design.

If you hate writing code from scratch then Flexy Boxes can help. It’s a free code generator that works like a flexbox playground. You tweak a few settings like the flex container, total columns, and content order.

From there you just copy/paste the code into your site and bam! You’ve got a fresh standards-compliant flexbox layout ready to go.

Just note it helps to already understand flexbox before using this webapp. If you’re looking for a place to start I recommend this tutorial on

Grid Generator

Every great site needs a working grid system. This comes pre-packaged with many frontend frameworks like Bootstrap so you won’t always need to build custom grids from scratch.

But if you do then this Responsive Grid Calculator is a handy code generator to keep saved. It takes a simple input of the # of columns along with the margin percent values, then auto-calculates the code needed to create a grid with that setup.

Note this calculator works on percents so it is not a fixed grid system. You have the choice to setup a max-width property but these grids can fit into any size website.

CSS3 Generator

My personal favorite in this list is the CSS3 Generator. It is by far the most expansive tool with dozens of custom settings you can tweak for code output.

You’ll find close to 15+ code generators for various CSS3 features such as:

  • Box shadows
  • CSS transforms
  • rgba() color codes
  • Flexbox layouts
  • CSS3 gradients

You just click on whatever you want to create, enter some settings, and let this CSS3 generator go to work. It’ll tell you exactly which features work in which browsers so you can also decide if you need fallbacks.

CSS Button Generator

From CTA buttons to email signups there’s good reason to build catchy CSS3 buttons. But why spend time reinventing the wheel?

This free CSS button generator is the perfect way to create codes that work and offer easy extensibility. By default you can pick from dozens of color schemes and custom gradients. Some use drop shadows, others use border effects or 3D style click effects.

Best of all this webapp works like an in-browser editor so you can change features right in your browser. The output code also updates immediately so you can copy/paste and reuse for whatever purpose you like.

Base64 Encode

With this Base64 image webapp you can encode pretty much any picture you need into base64 code.

If you don’t know base64 is an encoding type that can encode data textually. This lets you convert images into text and embed them directly into CSS. This is great for repeating backgrounds, smaller icons, and pretty much anything that you’d add into your stylesheet.

The majority of base64 code is much smaller than any image file. This is why it’s to your advantage to encode images into base64 whenever possible. You cut down on HTTP requests and load fewer KBs per page.

And with this free webapp it’s easier than ever to get started.

CSS Animate

It used to be that JavaScript was the only way to create page animations. But with CSS3 you can rely on transitions + keyframe animations to create amazing motion in your web browser.

And with CSS Animate you don’t even need to write the code yourself. This free tool lets you create animations by dragging & dropping a block element on a visual animation timeline.

Using the side panel you can adjust the animation timing, speed, position, and even animation styles like rotations.

This is totally free to use and it auto-generates the proper CSS3 code for getting these animations working right. I absolutely recommend bookmarking this tool if you do a lot of custom animation work.


Stylie is a completely free web animation tool powered by GitHub. This means the source code is available for download if you wanna learn more.

But you certainly don’t need to do anything on GitHub to get value value from Stylie. It’s an in-browser animation code generator where you can create your own CSS3 easings, keyframes, or pretty much anything else.

And you get the final output in HTML/CSS which you can just copy into your projects to keep rolling.

This is perhaps the simplest web animation tool on the net. It has the easiest interface to learn and it’s something you can reuse many times over.


Even though CSSmatic is a bit small with only 4 tools, it’s also one of the more unique CSS code generators. These tools are super easy to use and they come with lots of options.

You can generate rounded corners, box shadows, CSS3 gradients and most interestingly custom noise with any BG color you like.

It’s super simple to learn and the gradient tool is especially valuable if you’re looking for preset gradients.


CSS sprites are still widely used to cut down on HTTP load times. Designers typically create their own sprite sheets with programs like Photoshop by adding lots of icons/images into one file.

Now with SpriteGen you can save all that manual labor and automate the process. It’s a totally free webapp that lets you upload files(max 32MB) from your computer. Then SpriteGen organizes these files into the smallest sprite possible and outputs the final image.

It’s always a transparent PNG so this works great for CSS icons. And this has a sister app for responsive sprites if you’d like to test that out too.

CSS Center

Centering an HTML object isn’t too difficult. But there are many different ways to achieve this depending on the container size and the element’s position(absolute, relative, or maybe floated).

There’s an awesome free webapp called How To Center in CSS which does exactly as the name suggests. You run through a series of questions answering details about how you want to center something on the page. Then you’ll get some code that you can copy/paste into your stylesheet.

The great thing about this app is how it generates the code in so many formats. You can get the full HTML & CSS for centering anything on the page both horizontally and vertically! If you’ve ever tried to vertically center anything with CSS you’ll know why this app is so valuable.

This can absolutely save you loads of time and it’s fully up-to-date with the latest CSS techniques including flexbox.

Wrapping Up

All of these tools are phenomenal and they each solve different problems. But remember that code generators are only tools. They should be used to help you save time, but not used to avoid learning CSS.

If you’d like to sharpen your CSS skills take a peek at our recommended webapps ranging from games to online IDEs. All of these can help to improve your CSS knowledge right from your web browser.

About the Author Jake Rocheleau

Jake is a passionate writer & digital designer frequently researching the latest trends in UI/UX design and user behaviors. You can find work samples on his portfolio and follow his tweets @jakerocheleau.