When it comes to the development of websites and the design of content, understanding the difference between the Border-Box and the Content-Box can be a major help. For anyone, who works with web design and development, it's important to have an understanding of the two models so that you can optimize this information for SEO.
Understanding the Basics
Put simply, the Border-Box model includes both the border and padding of an element, in the total width and height of the element. This will mean that if you set the width of an element that includes a 20px padding, the border-box model will add the 20px of padding to the element's width, which means that it will be smaller than the normal width.
For the Content-Box model, the padding and the border of an element isn't included in the total width and height of the element. So, compared to the border-box model, the content-box object will be larger due to the padding and border being excluded from the width and height.
Now that we understand the basics of the models, let's look at the difference between them in more detail.
Border-Box Model
When using the Border-Box model, the padding and border are included in the size of an element, as previously mentioned. This means that any padding, or content inside of the element, will be contained within the given height and width of an elements.
This is different to the Content-Box model, which doesn't include the border or padding and instead, the height and width of the element will be larger due to only measuring the outer edges of the content inside.
Also, an element that uses the border-box model will normally remain the same size as it's given, regardless of how you manipulate it.
Content-Box Model
The Content-Box model includes the outer edge of an elements content. So, the width and height of an element will change when the element's content changes.
Also, when using the border-box model, it's possible that the content of the element could, possibly, go outside of the element's frame due to the padding not being included; whereas with the content-box model, this isn't a problem as the padding isn't included when measuring the width and height of an element.
How are They Related to SEO?
Using either of these models can matter when optimizing your website for SEO.
Search engines use algorithms when crawling the web, and checking the size of elements can help them understand how the webpage is organized and the hierarchy of the content.
Due to this, if you use the border-box model to give an element a size that is specific to the content inside of it, then it's likely that the search engines will see it as such.
On the other hand, if you use the content-box model then the size of the element can change to different sizes, depending on how the content is changed. This can be confusing for search engines and they may not be able to fully understand the content hierarchy of the page.
FAQ
What is a Border-Box?
A Border-Box is a model for websites and content design that includes both the padding and border of an element in the total size of the element.
What is a Content-Box?
A Content-Box is a design model that doesn't include the border or padding in the size of the element. The size of the element will increase when the content of the element changes.
What is the Difference Between the Two?
The main difference between a Border-Box and a Content-Box is that with the Border-Box model, the padding and border are included in the size of the element, whereas with the Content-Box the padding and border are excluded from the size of the element and essentially, ignored. This means that the size of an element with a Border-Box might stay the same, while an element with a Content-Box will increase when the content of the element changes.
What Do They Mean for Web Design and Development?
Border-Box and Content-Box models can have an important effect on web design, as they can affect the size and layout of elements when designing content for a page. When designing a page, it's important to consider which model will work better for the content, as this will help create an organized and effective page design.
How are They Related to SEO?
Search engines use algorithms when crawling the web, and checking the size of elements can help them understand how the webpage is organized and the hierarchy of the content. Border-Box and Content-Box can have a direct effect on how the content is optimized for SEO as one may be more organized and effective than the other.