However. I have now got zillions of tomato plants that have sprung up, self seeded from last years lot, I assume, though most nowhere near where they were last year!

anyway, I carefully dug them out, and potted them up, and most have survived and thrived.
The question is
As these have to stay in pots/containers what is the minimum size of pot container for them to thrive, and produce some fruit? Obviously ( I asssume) the bigger the better, but what is the minimum you exprts would consider a decent size ?
Might have to sacrifice some if there arent enough big containers!