Cartesian product calculator: read each line as a set and list every combination produced by multiplying all sets together (A x B x C ...), together with the exact size of the product.

How to use:
1. Type one set per line with elements separated by commas or spaces, for example:
   1,2,3
   4,5
2. Tune the parameters as needed:
   - Joiner: how elements inside a combination are glued together; leave it empty to concatenate directly (1 and 4 become 14), which is handy for building long IDs;
   - Output separator: defaults to one combination per line, or use , to keep everything on a single line;
   - Group display: wrap each element in parentheses (1)-(4) or square brackets [1]-[4] so you can see which set it came from;
   - Max results: the upper bound on how many combinations are listed (1 to 20000);
3. Hit Run and the summary states "Output N, Total M combinations" while the table lists every index and combination.

Difference from the Multi-line Permutation Generator: this tool is about the cross product of several sets, and focuses on a custom joiner (which may be empty), grouped display and an explicit statement of the product size.

Scale guards: at most 12 sets, 200 elements per set, 20000 listed combinations and 200,000 output characters. Beyond a limit the tool silently folds the input back and shows a notice, while the summary still reports both the number of combinations printed and the theoretical total.