count a word in dataGridView

Please check the below link it might help.

https://www.aspsnippets.com/questions/209277/Count-number-of-record-for-specific-string-in-DataGridview-row-using-C-and-VBNet-in-Windows-Forms-Application/

Also this might help.

int x = 4;

    lblRows2.Text = (from Rows in DataGridView1.Rows.Cast()
                     where !Rows.IsNewRow && Rows.Cells(x).Value.ToString == "Mercedes"
                     select Rows).Count;