Free, no account, no ads. Your class list is stored in this browser and never sent anywhere.
Twenty-three children in groups of four is not five fours and a three sitting on its own at the end. The simple approach — take four, take four, take four — leaves the leftover bunched, and because the list is usually alphabetical it is the same three children every time.
This deals them round-robin instead, so sizes differ by at most one and the smaller groups are spread through the set. Twenty-three into six groups comes out as four fours and two threes, not five fours and a stray.
Type the pairs that should not share a table and the generator will try every arrangement it can to honour them. If it genuinely cannot with the number of groups you asked for, it says so rather than quietly ignoring you.
Those pairs are never rendered on screen. That is not a detail — the whole class is looking at the board, and a list of who is not allowed to sit with whom is not something to project. They stay in the box below the fold, on your machine.
Groups of four and six groups are different questions and teachers need both. Groups of a size is what you want when the constraint is equipment — six microscopes, four tablets. A number of groups is what you want when the constraint is the room or the activity.
Re-rolling until it looks right is normal and not a misuse. The button is one click and keeps your keep-apart pairs.
Yes. Enter them as a pair and the generator works around it. The pairs are never displayed on screen, so nothing is revealed to the class.
They are spread across the groups rather than left in a small group at the end, so sizes never differ by more than one.
Indirectly — ask for a number of groups rather than a size, and the remainder is distributed for you.