Moving from Seedling Cup to a Pot

First time grower here, i have 4 little seedlings in party cups, at how many inches should i tranfer them to there big pots?

when ever the roots start showing through the bottom... i usually transplant at 2 and a hals weeks to 3 weeks

first time grower with very little seeds shouldnt transplant, just get buckets of dirt, germinate and plant. if u transplant and 1 dies u will feel bad and u lose alot of potential crop. that said, just take d6520's advice, just make sure to water them afterwards

Don't go over two weeks you are just stunting them they will grow faster in bigger pots.