What is the difference among col-lg-* , col-md-* and col-sm-* in Twitter Bootstrap?
Updated 2020...
Bootstrap 5
In Bootstrap 5 (alpha) there is a new -xxl- size:
col-* - 0 (xs)
col-sm-* - 576px
col-md-* - 768px
col-lg-* - 992px
col-xl-* - 1200px
col-xxl-* - 1400px
Bootstrap 5 Grid Demo
Bootstrap 4
In Bootstrap 4 there is a new -xl- size, see this demo. Also the -xs- infix has been removed, so smallest columns are simply col-1, col-2.. col-12, etc..
col-* - 0 (xs)
col-sm-* - 576px
col-md-* - 768px
col-lg-* - 992px
col-xl-* - 1200px
Bootstrap 4 Grid Demo
Additionally, Bootstrap 4 includes new auto-layout columns. These also have responsive breakpoints (col, col-sm, col-md, etc..), but don't have defined % widths. Therefore, the auto-layout columns fill equal width across the row.
Bootstrap 3
The Bootstrap 3 grid comes in 4 tiers (or "breakpoints")...
Extra small (for smartphones .col-xs-*)
Small (for tablets .col-sm-*)
Medium (for laptops .col-md-*)
Large (for laptops/desktops .col-lg-*).
These grid sizes enable you to control grid behavior on different widths. The different tiers are controlled by CSS media queries.
So in Bootstrap's 12-column grid...
col-sm-3 is 3 of 12 columns wide (25%) on a typical small device width (> 768 pixels)
col-md-3 is 3 of 12 columns wide (25%) on a typical medium device width (> 992 pixels)
The smaller tier (xs, sm or md) also defines the size for larger screen widths. So, for the same size column on all tiers, just set the width for the smallest viewport...
<div class="col-lg-3 col-md-3 col-sm-3">..</div> is the same as,
<div class="col-sm-3">..</div>
Larger tiers are implied. Because col-sm-3 means 3 units on sm-and-up, unless specifically overridden by a larger tier that uses a different size.
xs(default) > overridden by sm > overridden by md > overridden by lg
Combine the classes to use change column widths on different grid sizes. This creates a responsive layout.
<div class="col-md-3 col-sm-6">..</div>
The sm, md and lg grids will all "stack" vertically on screens/viewports less than 768 pixels. This is where the xs grid fits in. Columns that use the col-xs-* classes will not stack vertically, and continue to scale down on the smallest screens.
Resize your browser using this demo and you'll see the grid scaling effects.
This article explains more about how the Bootstrap grid
The bootstrap docs do explain it, but it still took me a while to get it. It makes more sense when I explain it to myself in one of two ways:
If you think of the columns starting out horizontally, then you can choose when you want them to stack.
For example, if you start with columns:
A B C
You decide when should they stack to be like this:
A
B
C
If you choose col-lg, then the columns will stack when the width is < 1200px.
If you choose col-md, then the columns will stack when the width is < 992px.
If you choose col-sm, then the columns will stack when the width is < 768px.
If you choose col-xs, then the columns will never stack.
On the other hand, if you think of the columns starting out stacked, then you can choose at what point they become horizontal:
If you choose col-sm, then the columns will become horizontal when the width is >= 768px.
If you choose col-md, then the columns will become horizontal when the width is >= 992px.
If you choose col-lg, then the columns will become horizontal when the width is >= 1200px.
From Twitter Bootstrap documentation:
small grid (≥ 768px) = .col-sm-*,
medium grid (≥ 992px) = .col-md-*,
large grid (≥ 1200px) = .col-lg-*.
Let's un-complicate Bootstrap!
Notice how the col-sm occupies the 100% width (in other terms breaks into new line) below 576px but col doesn't. You can notice the current width at the top center in gif.
Here comes the code:
<div class="container">
<div class="row">
<div class="col">col</div>
<div class="col">col</div>
<div class="col">col</div>
</div>
<div class="row">
<div class="col-sm">col-sm</div>
<div class="col-sm">col-sm</div>
<div class="col-sm">col-sm</div>
</div>
</div>
Bootstrap by default aligns all the columns(col) in a single row with equal width. In this case three col will occupy 100%/3 width each, whatever the screen size. You can notice that in gif.
Now what if we want to render only one column per line i.e give 100% width to each column but for smaller screens only? Now comes the col-xx classes!
I used col-sm because I wanted to break the columns into separate lines below 576px. These 4 col-xx classes are provided by Bootstrap for different display devices like mobiles, tablets, laptops, large monitors etc.
So,col-sm would break below 576px, col-md would break below 768px, col-lg would break below 992px and col-xl would break below 1200px
Note that there's no col-xs class in bootstrap 4.
This pretty much sums-up. You can go back to work.
But there's bit more to it. Now comes the col-* and col-xx-* for customizing width.
Remember in the above example I mentioned that col or col-xx takes the equal width in a row. So if we want to give more width to a specific col we can do this.
Bootstrap row is divided into 12 parts, so in above example there were 3 col so each one takes 12/3 = 4 part. You can consider these parts as a way to measure width.
We could also write that in format col-* i.e. col-4 like this :
<div class="row">
<div class="col-4">col</div>
<div class="col-4">col</div>
<div class="col-4">col</div>
</div>
And it would've made no difference because by default bootstrap gives equal width to col (4 + 4 + 4 = 12).
But, what if we want to give 7 parts to 1st col, 3 parts to 2nd col and rest 2 parts (12-7-3 = 2) to 3rd col (7+3+2 so total is 12), we can simply do this:
<div class="row">
<div class="col-7">col-7</div>
<div class="col-3">col-3</div>
<div class="col-2">col-2</div>
</div>
and you can customize the width of col-xx-* classes also.
<div class="row">
<div class="col-sm-7">col-sm-7</div>
<div class="col-sm-3">col-sm-3</div>
<div class="col-sm-2">col-sm-2</div>
</div>
How does it look in the action?
What if sum of col is more than 12? Then the col will shift/adjust to below line. Yes, there can be any number of columns for a row!
<div class="row">
<div class="col-12">col-12</div>
<div class="col-9">col-9</div>
<div class="col-6">col-6</div>
<div class="col-6">col-6</div>
</div>
What if we want 3 columns in a row for large screens but split these columns into 2 rows for small screens?
<div class="row">
<div class="col-12 col-sm">col-12 col-sm TOP</div>
<div class="col col-sm">col col-sm</div>
<div class="col col-sm">col col-sm</div>
</div>
You can play around here: https://jsfiddle.net/JerryGoyal/6vqno0Lm/
I think the confusing aspect of this is the fact that BootStrap 3 is a mobile first responsive system and fails to explain how this affects the col-xx-n hierarchy in that part of the Bootstrap documentation.
This makes you wonder what happens on smaller devices if you choose a value for larger devices and makes you wonder if there is a need to specify multiple values. (You don't)
I would attempt to clarify this by stating that...
Lower grain types (xs, sm) attempt retain layout appearance on smaller screens and larger types (md,lg) will display correctly only on larger screens but will wrap columns on smaller devices.
The values quoted in previous examples refer to the threshold as which bootstrap degrades the appearance to fit the available screen estate.
What this means in practice is that if you make the columns col-xs-n then they will retain correct appearance even on very small screens, until the window drops to a size that is so restrictive that the page cannot be displayed correctly.
This should mean that devices that have a width of 768px or less should show your table as you designed it rather than in degraded (single or wrapped column form).
Obviously this still depends on the content of the columns and that's the whole point. If the page attempts to display multiple columns of large data, side by side on a small screen then the columns will naturally wrap in a horrible way if you did not account for it. Therefore, depending on the data within the columns you can decide the point at which the layout is sacificed to display the content adequately.
e.g. If your page contains three col-sm-n columns bootstrap would wrap the columns into rows when the page width drops below 992px.
This means that the data is still visible but will require vertical scrolling to view it. If you do not want your layout to degrade, choose xs (as long as your data can be adequately displayed on a lower resolution device in three columns)
If the horizontal position of the data is important then you should try to choose lower granularity values to retain the visual nature. If the position is less important but the page must be visible on all devices then a higher value should be used.
If you choose col-lg-n then the columns will display correctly until the screen width drops below the xs threshold of 1200px.
TL;DR
.col-X-Y means on screen size X and up, stretch this element to fill Y columns.
Bootstrap provides a grid of 12 columns per .row, so Y=3 means width=25%.
xs, sm, md, lg are the sizes for smartphone, tablet, laptop, desktop respectively.
The point of specifying different widths on different screen sizes is to let you make things larger on smaller screens.
Example
<div class="col-lg-6 col-xs-12">
Meaning: 50% width on Desktops, 100% width on Mobile, Tablet, and Laptop.
Device Sizes and class prefix:
Extra small devices Phones (<768px) - .col-xs-
Small devices Tablets (≥768px) - .col-sm-
Medium devices Desktops (≥992px) - .col-md-
Large devices Desktops (≥1200px) - .col-lg-
Grid options:
Reference: Grid System
.col-xs-$ Extra Small Phones Less than 768px
.col-sm-$ Small Devices Tablets 768px and Up
.col-md-$ Medium Devices Desktops 992px and Up
.col-lg-$ Large Devices Large Desktops 1200px and Up
One particular case : Before learning bootstrap grid system, make sure browser zoom is set to 100% (a hundred percent). For example : If screen resolution is (1600px x 900px) and browser zoom is 175%, then "bootstrap-ped" elements will be stacked.
HTML
<div class="container-fluid">
<div class="row">
<div class="col-lg-4">class="col-lg-4"</div>
<div class="col-lg-4">class="col-lg-4"</div>
</div>
</div>
Chrome zoom 100%
Browser 100 percent - elements placed horizontally
Chrome zoom 175%
Browser 175 percent - stacked elements
well it's used to tell bootstrap how many columns are to be placed in a row depending on the screen size-
col-xs-2
would show only 2 columns in a row in extra small(xs) screen, in the same way as sm defines a small screen, md(medium sized), lg(large sized),
but according to bootstrap smaller first rule, if you mention
xs-col-2 md-col-4
then 2 columns would be shown in every row for screen sizes from xs upto sm(included) and changes when it gets next size i.e. for md up to lg(included)
for a better understanding of screen sizes try running them in various screen modes in chrome's developer mode(ctr+shift+i) and try various pixels or devices
What is the difference in between below two methods?
Method #1
<div class="col-xs-12 col-sm-12 col-md-12 col-lg-12 col-xl-12">
</div>
Method #2
<div class="col-md-12">
</div>
I'm using the second method and it works for all small and large devices perfectly then when do i need the first method?
This is a good question. I see a few others have answered it already, but I'd like to go a little bit more in depth in case you're curious.
In method 2, you're specifically saying "I want this container to take up the full 12 at 970px and above. Since it's a full 12, though, it will retain the full-width 12 all the way down to the smallest resolution. If, however, you had two col-md-6's, the 6's would become 12's when the screen goes below 970px due to the use of md.
In your first method, you're explicitly stating that you want the column to be the full 100% at all the breakpoints.
To answer your question "Why do I need the first method?", you simply don't. The first method is overkill since bootstrap will make them all 100% by default anyways. The only reason you would want to use something like the first method is if you want to show the content in different layouts at different resolutions.
For example:
<div class="col-sm-6 col-md-3">
</div>
This would make the column a 3 at all resolutions 992px and above (because of the md). By default, bootstrap would make the column a full 12 below 992px using the col-md-3 class but with the declaration of col-sm-6, you're overwriting it and making it a 6 on all resolutions between 768px and 992px. Everthing below 768px (col-xs-*) would still make the column a full 12. You could overwrite this by declaring a 'col-xs-*' class just as you did with the 'col-sm-6'
If a smaller resolution is not explicitly stated, it's going to be a 12. Anything you declare will apply to that resolution and above with the exception of the xs. xs will declare 768px and below.
Here is the official bootstrap documentation to show the grid options and their associated resolutions:
https://getbootstrap.com/css/#grid-options
Here's a bootply to help visualize this:
http://www.bootply.com/c0KgRryXcl
I hope that helps!
You won't notice a difference with col-md-12 as it's the full width of the container, but if you had 2 col-md-6's, they would look squished together on a small device, hence why you'd use col-xs-12, then the breakpoint would kick in and it would change from 50% to 100%.
The first method is useful if you want to change your proportions of divs when on a smaller device.
For example, you may have the following
<div class="row">
<div class="col-xs-12 col-md-6">
</div>
<div class="col-xs-12 col-md-6">
</div>
</div>
So on a small device, instead of each occupy half of the width (which will be small), the two columns will be stacking up
These classes are used for different devices resolution. your first method includes all devices like mobile , laptops, desktops and larger and second method includes only desktop.
This are grid classes in bootstrap,
xs (for phones)
sm (for tablets)
md (for desktops)
lg (for larger desktops)
The classes above can be combined to create more dynamic and flexible layouts.
<div class="col-xs-12 col-sm-12 col-md-12 col-lg-12 col-xl-12">
</div>
Bootstrap's grid system allows up to 12 columns across the page.
but 12 columns each row. Your code have added 60 columns in one row its wrong.
Basic Structure of bootstrap grid:
<div class="row">
<div class="col-*-*"></div>
<div class="col-*-*"></div>
<div class="col-*-*"></div>
</div>
I have a div tag like as below.
<div class="col-xs-5 col-md-2 col-lg-1"></div>
With the current resolution of window / device how would I know if it is going to apply either col-xs-5 or col-md-2 or col-lg-1.
The reason for this question is I have to request number of items to the server. If the bootstrap applies col-xs-5 I'll request 10 Items. Otherwise 20 items, 30 items respectively.
Is there any way I'll know which class is going to apply to my DIV tag ?
you need to take a look at the info found on their website http://getbootstrap.com/css/#grid
but what is happening is that when the div has <div class="col-xs-5 col-md-2 col-lg-1"></div> these class names it will apply them based on screen size. bootstrap works on a 12 column grid system so if you use col-xs-5 then it will only fill up 5 of those columns when the width of the screen is xs(mobile) then once the screen hits a medium sized screen it will only fill up 2 of those columns if you are using the col-md-2.
This doesnt actually change anything within your html its just reajusting the size of it.
For example there is a way to hide everything within a div at a certain screen size usig hidden. so if you wanted to hide everything at screen size xs then you would use a div class called hidden-xs this doesnt actually delete what you have on the screen but like its name it "hides" it.
btw the screen sizes for each class are as follows:
Extra small devices Phones (<768px)
Small devices Tablets (≥768px)
Medium devices Desktops (≥992px)
Large devices Desktops (≥1200px)
Bootstrap will let you style content differently based on device width, but if you want to load different/more/less content, you can detect the width with jQuery. Probably best to use the same breakpoints as Bootstrap to keep things consistent. Then somehow load that content you want based on the if statement that is true:
var width = $(window).width();
if (width < 767){
// load your "xs" content
} else if ((width >= 768) && (width < 991)) {
// load your "sm" content
} else if ((width >= 992) && (width < 1200)){
// load your "md" content
} else {
// load your "lg" content
}
That being said, bootstrap also allows for show/hide at different device widths, which could also solve your problem, but with quite a bit of additional markup.
Adding .col-xs-12 makes my element take up 100% space not only in mobile, how do I make it narrower on desktop? Should I nest additional column classes like .col-md-4 and such?
This is what it looks like on desktop:
.col-xs-12 will render as the default for all viewport sizes if you don't specify a different value for larger screens (eg .col-lg-4 / .col-md-6 / .col-sm-8)
Without seeing your code I can't tell what you are actually trying to achieve, but if you only want the bar to take up 50% in laptop/desktop views for example you would have the html as follows:
<div class="col-md-6 col-xs-12">
Keep in mind that you will need to balance out your grid in the larger views if you go this way (12 columns within the row) http://getbootstrap.com/css/#grid-options
I'm not quite following you but I think you're after the following behaviour
<div class="col-md-6 col-sm-12 col-xs-12">
this will allow for full width on xs and sm viewports
I'm learning about the grid in Twitter Bootstrap 3 and there's something I don't understand...sorry if this is a dumb question.
I understand that media queries make the width of the container class different each time eg. a viewport with a minimum width of 768px makes the container class be 750 px wide. ....a viewport with a minimum width of 1200px makes the container class be 1170px etc.
However why is there a need to have different classes for columns such as .col-md-2 and .col-lg-2 as in both these cases the value is 8.333333333333332%; and then .col-md-3 and .col-lg-3 are both 25% and so on
25% of 750px would still give you propotionally the same as 25% of 1170px
You have four different classes so you can have four different layouts, depending on screen size.
The key part of the Bootstrap grid system that I see most people misunderstanding is that you do not need all four classes - xs, sm, md, and lg. The browser will take the smallest one and apply that until it reaches a larger one.
So for instance, col-xs-4 would be applied at all screen sizes if no other sizes are ever applied. Adding col-sm|md|lg-4 to the same div is completely unnecessary.
As a side note, I also see col-xs-12 col-sm-4 a lot as well, which is also unnecessary. col-xs-12 is implied if you set a sm or larger class. Actually, 12 column is implied for any size smaller than the smallest declared. So if you just put col-lg-4, then col-xs|sm|md-12 is implied.
So if you want your layout to look exactly the same at all resolutions, just use xs. If you want it to look a certain way on tablets and up, but just be stacked on phones, then just use sm. If you want that div to be 3 on phones, 4 on tablets, and 6 on desktops and up, then you need col-xs-3 col-sm-4 col-md-6.
.col-xs-, .col-sm-, .col-md-, and .col-lg- all refer to different viewport sizes for there columns each is there so you can set your columns different on different devices. If you refer to this table (http://getbootstrap.com/css/#grid-options) it will show you each size that corresponds to each one of the differing classes.
Basically they look and act the same as you pointed out, but they are set up using different media queries so they differ in this factor. This is so you can have different spanning columns on different devices. let's say you like a column span of four for your medium to large devices a span of six for your small/tablet devices and a span twelve for your extra-small/phone devices. You should only have to worry about your medium and small devices in this case the large will inherit it's span from your medium declaration and the extra-small should automatically be 12 if not set. (I'm not positive on that last part but that's what it seems to be.)
So all you have to do is add .col-md-4 to all your divs as well as a .col-sm-6 and this will execute the above said layout.