Cell Seeding Calculator
Plan a plate: the volume of cell suspension and medium to mix so that every well receives the same number of cells, with extra for pipetting loss.
Formula
- number of cells each well should receive
- percentage added to cover pipetting loss
How it works
Rather than adding cells to each well separately, one seeding suspension is prepared at the concentration that delivers the required cells in the volume dispensed per well. Every well then receives the same volume of the same mixture.
The extra percentage enlarges the batch so the reservoir does not run dry before the last wells.
Worked example
Seed 96 wells with 5,000 cells in 100 µL each, from a suspension at 1.06 × 10⁶ cells/mL, with 10% extra.
- Wells prepared for = 96 × 1.1 = 105.6, so the total volume is 10.56 mL.
- Cells needed = 105.6 × 5,000 = 5.28 × 10⁵.
- Suspension = 5.28 × 10⁵ / 1.06 × 10⁶ per mL = 498.1 µL.
Mix 498 µL of cell suspension with 10.06 mL of medium and dispense 100 µL per well.
These are the values the calculator opens with, so you can check its output against this example.
Assumptions
- The seeding suspension stays evenly mixed while it is dispensed.
- Cells per well refers to viable cells if the stock concentration is a viable count.
Common mistakes
- Letting the reservoir stand. Cells settle and the last columns receive fewer than the first; mix between rows.
- Ignoring edge effects. Outer wells evaporate faster, which changes growth independently of seeding.
- Seeding by cells per well when the experiment is defined per unit area. Use the cells per cm² calculator for that.
Related tools
Related equipment
Service documentation, failure modes and parts for the instruments this calculation is used with.