But they are not all the same, most follow the IPak Standard, developed in the 1870s in Lucknow, spread by Taj Ltd Company (founded 1929 in Lahore, before partition with presses in Delhi and Bombay, twice bankrupt, twice reborn), today reprinted in South Africa, the UK, the States, Bangla Desh and the Republic of India.
The biggest sub-group are the Indonesian prints, falling into Bombay reprints, Ottoman reprints (called Bahriye), after 1983, after 2002, after 2018 standard prints. About thirty Muslim scholars debated for fifteen years before publishing the 1983 "Standar Indonesia," since twice revised.
There are difference within India too, unimportant differences like the shape of sukun
Here from left to right: from an old Delhi print, a modern Taj Co Ltd print, from Bombay, from Lucknow, from Madras, (second line:) from Punjab, Calcutta 1831 and 2010, and from Kerala. So besides the typical head of jīm without the dot, one finds circumflex (in Calcutta the rule) and (MSA and Ottoman) circle.
Here from left to right: from an old Delhi print, a modern Taj Co Ltd print, from Bombay, from Lucknow, from Madras, (second line:) from Punjab, Calcutta 1831 and 2010, and from Kerala. So besides the typical head of jīm without the dot, one finds circumflex (in Calcutta the rule) and (MSA and Ottoman) circle.
More important differences like the iẓhār nūn in Bombay and Kerala
Below printed 1883 in Tellicherry (now: Thalassery), same closeness to Ottoman rasm:
and quite different one: in Kerala, both sukun and rasm are close to Ottoman maṣāḥif:
The places, where Kerala writes like the Ottomans are surrounded in blue, were not in green ‒ on the left margin, below: hamza in a Calcutta, a Bombay and a Lahore print.
From about 1950 till today printed in
Tirurangadi.Below printed 1883 in Tellicherry (now: Thalassery), same closeness to Ottoman rasm: