Is there a recommended maximum line length for HTML or JavaScript? [closed]

Answer 1

The 80 character line limit spawns from the days of screens without a lot of real estate. Now it's just like that for readability, and so it's possible to have two (or more) different code files opened side-by-side, without having to scroll to see each of them.

Those reasons still apply to HTML and JavaScript, although, it's obviously not necessary to comply with them. So it's up to you.

I agree that with HTML it can be difficult to keep within that limit, although with JavaScript it shouldn't be a problem.

Answer 2

The maximum limit on line length is whatever you feel comfortable reading and editing. personally, any code of mine that won't fit on the screen without wrapping will be rewritten.

Answer 3

Google says 500-ish for JS: https://developers.google.com/closure/compiler/faq#linefeeds

The Closure Compiler intentionally adds line breaks every 500 characters or so. Firewalls and proxies sometimes corrupt or ignore large JavaScript files with very long lines. Adding line breaks every 500 characters prevents this problem.

uglify --max-line-len 500 or grunt-contrib-uglify options: { maxLineLen: 500 }

I'm not sure if the limit applies to HTML or CSS, but I haven't seen that option for any CSS compressor I've used.

SMTP rules would apply to HTML email: https://www.ietf.org/rfc/rfc0821.txt

The maximum total length of a command line including the command word and the CRLF is 512 characters.

Answer 4

Many "services" (eg Some terminal window implementations, GitHub, etc) will not wrap long lines and do not have scroll bars.
So anything beyond past 72 or 80 chars can simply get cut off.

Also, it just helps for readability even if there are scrollbars, code can be easier to read/digest/debug if it can fit on (or mostly on) a single screen width.

So while, the code will run, it may not always be able to be displayed in its entirety.

Answer 5

How about putting all of the HTML on one line? How will browsers cope with that? I've read somewhere that some browser (can't remember which one) breaks with long lines.

Stripping new lines from the file is an optimisation technique. You don't need to give clients the same easy-to-read version that you use when you develop it. You can give them a stripped version. Why? Bandwidth is not free.

Answer 6

This limit seems to be a legacy from ancient IBM punch cards. Why is 80 characters the 'standard' limit for code width?

I really find it hard to work with only 80 characters for HTML. It gets unreadable really fast. So I decided for myself to take the line length on GitHub as measurement.

There seem to be different character limits depending on OS and/or browser. But 120 should be a quite safe value.

On Ubuntu:

• Firefox: 126
• Opera 12.16: 126
• Chromium: 113

On OSX 10.9:

• Google Chrome: 125
• Firefox: 122
• Safari: 121

Source: What is Github's character limit, or line length for viewing files on github?

---

On the other hand sometimes choosing your own standard doesn't work. Coding standards or linters for your language or framework might force you to stick to 80 characters. Which at least can be really helpful when it comes to reading code on mobile screens.

But for HTML I'd devo rise this number to 120 characters. For the sake of readability. I mean think of all the CSS-class-heavy frameworks like Bootstrap, what would your template look like in the end with only 80 characters line length? (Apart from that you'd better choose Bourbon Neat which won't pollute your HTML with tons of classes.)