Image Click Counter

Places a numbered marker on a photo each time you click a cell, particle or colony, and keeps a count per category. Use it to count many objects by hand without missing any or counting one twice.

How to use

1. Drop the photo on the page, or click to choose it.
2. Under "Categories", set a name and "Marker shape"; press "Add category" for more kinds. Number keys 1 to 9 switch categories.
3. With the "Count" tool, click each object. Drag a marker to move it; right-click or long-press to delete it.
4. To count by area, turn on "Show a grid". For density, draw a region with "Set region of interest" and enter the "Scale".
5. Keep the result with "Save PNG with markers", "Save as CSV" or "Save work file (JSON)".

How it works

• The tool does not count automatically. "Suggest candidates (optional)" marks possible positions from brightness alone, so check every added marker.
• Density is the count ÷ the area of the region of interest, or of the whole image if there is none. Without a scale it is per px².
• A marker on a grid line counts in the cell whose top or left edge it sits on.
• The work file does not contain the image. Work on an image is also saved on this device automatically.

Questions and answers

How do I count cells in a microscope image?

Open the image and click once on each cell. With several categories, such as large and small cells, the table shows each count and its "Share".

Can I count by grid squares, as on a hemocytometer?

Yes. Turn on "Show a grid" and set "Columns" and "Rows" to see the count in each cell.

Does it count objects automatically?

No, because touching objects and stains make automatic counts unreliable. A helper can suggest candidates by brightness, which you confirm yourself.

Can I continue counting later?

On the same device, opening the same image brings the markers back. Elsewhere, load the work file and add the same image.