What this calculator does
This biology calculator estimates viable cell concentration, cells needed per vessel, total stock volume required, dilution factor, and media addition for consistent seeding. It supports common plates, flasks, dishes, and fully custom growth areas.
It is a planning tool. Always confirm density, attachment, recovery, and medium conditions with your wet-lab protocol.
Calculated plating plan
Results appear here after submission, above the form as requested.
| Output | Value | Unit |
|---|
Plating trend chart
The chart tracks cumulative viable cells and cumulative stock volume across the planned vessels.
Cell plating density inputs
Use the format selector for quick defaults or enter custom values manually.
Example data table
This sample uses the default six-well values already loaded in the calculator.
| Parameter | Example value | Notes |
|---|---|---|
| Total cell concentration | 1,200,000 cells/mL | Measured before viability adjustment. |
| Viability | 92% | Used to estimate viable concentration. |
| Available stock volume | 12 mL | Total suspension available for plating. |
| Target plating density | 25,000 cells/cm² | Desired viable cell density on the surface. |
| Growth area per well | 9.6 cm² | Typical six-well plate area. |
| Number of wells | 6 | Total wells to seed. |
| Final volume per well | 2 mL | Dispensed into each well after dilution. |
| Preparation overage | 10% | Helps compensate for pipetting loss. |
Formula used
1) Viable cell concentration
Viable concentration = Total concentration × (Viability ÷ 100)
2) Cells needed per vessel
Cells per vessel = Target density × Growth area per vessel
3) Total viable cells required
Total required viable cells = Cells per vessel × Vessel count × (1 + Overage ÷ 100)
4) Stock volume needed
Stock volume needed = Total required viable cells ÷ Viable concentration
5) Final preparation volume
Prepared plating volume = Final volume per vessel × Vessel count × (1 + Overage ÷ 100)
6) Media to add
Media to add = Prepared plating volume − Stock volume needed
7) Maximum vessel capacity
Maximum vessels possible = Available viable cells ÷ Cells per vessel, rounded down
How to use this calculator
- Select a culture format or keep the custom option.
- Enter the measured total cell concentration from your counter.
- Add viability, stock volume, and desired plating density.
- Confirm growth area, vessel count, and final volume.
- Set an overage percentage for pipetting and transfer loss.
- Press Calculate plating plan to view results above the form.
- Review warnings before plating, especially if stock is limiting.
- Use the CSV or PDF export buttons for records.
Frequently asked questions
1) What is cell plating density?
Cell plating density is the number of viable cells placed on each square centimeter of culture surface. It influences attachment, growth rate, morphology, and experimental reproducibility.
2) Why does viability matter?
Viability adjusts the raw count to the cells that can actually attach and grow. Using total cells alone can overestimate usable material and produce under-seeded cultures.
3) Should I use cells per well or cells per cm²?
Cells per cm² is usually better for comparing different vessels because it normalizes by surface area. Cells per well is convenient after the growth area is already known.
4) What does overage mean here?
Overage adds extra prepared suspension beyond the exact requirement. It helps cover pipetting loss, dead volume, and small transfer errors during plating.
5) What if the calculator says stock is insufficient?
Reduce vessel count, lower target density, increase stock concentration, or collect more cells. The warning appears when available viable cells or available stock volume cannot support the plan.
6) Can I use this for flasks and dishes?
Yes. The format selector includes common plates, flasks, and dishes. You can also switch to custom mode and enter any growth area, count, and final volume.
7) Does this replace a lab protocol?
No. It supports planning and documentation. You should still follow validated protocols for medium composition, passage timing, attachment conditions, and assay-specific seeding requirements.
8) Why can stock volume needed exceed final plating volume?
That means the suspension is too dilute for the requested density and final volume. You would need to concentrate cells, reduce density, or plate a larger final volume.