Aerospace Recommended Practice "ARP568" defines Uniform dash numbering for O-ring. In 1971 SAE replaced this name as AS568 (Aerospace Standard).
There are 2 classes of tolerances for Internal diameters. Most common c/s - 1.78, 2.62, 3.53, 5.33, 6.99 and some additional ARP 900.
Each 3 digit dash no. has a standard ID and C/s. 1st digit says c/s ("0 - 1.78"; "1 - 2.62"; "2 - 3.53";...)and remaining 2 digits is random numbering for which std. needs to be referred to identify the ID of O-ring.
ISO 3601 follows the same SAE Aerospace Size Standard dash nos. and also mentions the 2 different class of tolerances Class A and Class B.
This standard is commonly manufactured by all the O-ring manufacturers. It is best to use this standard as per my experience.
ISO 3601 also defines tolerance bands for other sizes too.
Of course many other standards as mentioned by others can be followed.
O-rings are very simple profile seals and do not have any limitation for any sizes. Hence can be manufactured for other c/s's and ID's based on the hardware packaging available in application.
Hope this helps
Thanks.