ActiveCell.Formula = "=MAX(F16:F25)" 'plage à adapter à ton cas
Dim matrice(4, 5) As Long
Dim i As Byte, j As Byte
For i = 0 To 4
For j = 0 To 5
matrice(i, j) = Int(Rnd * 1000)
Next j
Next i
Range("a1:e5") = matrice
MsgBox Application.Max(matrice)