Size and colour order split planner
Turn a size mix into whole units that add up exactly to your order quantity. Add colours too if you want a grid. If your numbers do not add up, the tool stops and tells you by how much instead of quietly fixing them.
Method (largest remainder)
Exact units = order quantity × share ÷ total of all shares
Round every row down, then give each leftover unit to the row with the largest fractional part. Ties go to the larger share, then the earlier row.
Result
Enter an order quantity and a share for each size.
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