Sort of.
There are many UN (and other international agency) Commissions that work on this. The "three mile limit" is generally for national law that has not been agreed in the International courts as having effect over other countries.
There are some countries that claim much further, and it varies according to the aspects being considered. For example, Icelandic fishing rights are claimed for 200 miles around their coast, which upsets the British, since it overlaps some of our claims for fishing.
Then, we claim much of the Antarctic because we own an Island not far off the coast, which is inhabited (for about 20 days each year, if the weather is OK).
One law that extends everywhere concerns piracy. It is ilegal no matter how far out to sea it takes place. Any country, any vessel is entitled to take action under a UN Convention.
And so it goes on.