Hello Kirby Fawcett

The doubling time of HeLa cells can vary depending on the conditions, but it's generally between 17.5 and 36 hours. You need to know the doubling time of your cells.

In a 6-well plate, each well has a base surface area of 9.6 cm^2 and a working volume of 2 to 5ml. The cell density in a 6-well plate at confluency is 1.2 x 10 ^6. With this available data, if I consider the doubling time of HeLa cells as 33 hours, then for HeLa cells to reach confluency at a density of 1.2 x 10 ^6 within a week (7 x 24 hours= 168 hours), I will plate 0.04 x 10^6 (40000 cells) per well at 0 hour to reach confluency (1.28 x 10^6) after 165 hours (five doubling times: 33 hours x 5).

Please note: These numbers are expected only if the culture conditions are optimum for the growth of cells in culture.

Best.