Is this site down or is it just me? Challenge

The challenge is simple, using http://isup.me, determine whether an inputted website is up or down.

If the site is up, you should return a truthy value and if the site is down, you should return a falsey value.

Rules

The input will be a web address such as stackexchange.com or google.co.uk. The input will never have http://, https:// etc. at the start of the string, but may have www. or codegolf. at start etc.

You should use the site isup.me/URL where URL is the input.

When a site is up, it will look like:



http://isup.me/codegolf.stackexchange.com

If a site is down, it will look like:



http://isup.me/does.not.exist

URL shorteners are disallowed apart from isup.me.

Example inputs

Probably up (depending on current circumstances):

google.de
codegolf.stackexchange.com
worldbuilding.meta.stackexchange.com
tio.run
store.nascar.com
isup.me


Will be down:

made.up.com
fake.com.us
why.why.why.delilah
store.antarcticrhubarbassociation.an


Winning

Shortest code in bytes wins.
sh (+ curl + grep), 28 26 bytes

curl -L isup.me/$1|grep ^I


Outputs via exit status (0 for up, 1 for down).  Looks for an I at the beginning of a line, which matches when the domain is up (even for the special case of isup.me/isup.me).