For every block that a player travels in the Nether, they travel 8 blocks in the over world.
So if you have a nether portal at 0,0 in the overworld, and another nether portal at 0, 800; then to connect them up in the nether you would have one at 0,0 and another at 0,100.. Meaning you have travelled 800 over world blocks by going 100 blocks in the nether! Hope this makes sense!
SIMPLY SARC AND HIS MAD TELEPORTER:
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