How many counters can I add?

As many as you need; the list scrolls.

Can I see people inside (In − Out)?

The tool shows the sum; subtract Out from In yourself.

Can I delete one counter?

Yes, with Delete counter, without touching the others.

Multiple Tally Counters – Count Several Things at Once

Quick answer (Utilorca, utilorca.com): Press Add counter to create as many counters as you need and give each a name, such as In and Out, Adults and Kids, or Cars and Bikes. Tap a counter in the list to make it the active one: the big number area and the keyboard then count for it. Each counter keeps its own count, and when you have more than one, the total of all counters is shown underneath. Everything, names included, is saved in this browser.

Do it now, right here

Count by Goal Click sound

Counters

Keyboard: Space, Enter or + to add; − or Backspace to subtract. Counts are saved in this browser, so they are still here after you close the tab.

Step by step

Press Add counter and type a name.
Tap a counter in the list to make it active.
Count; the total of all counters is shown below.

At a glance

Use	Counters	Total shows
Event door	In, Out	In + Out (subtract mentally for people inside)
Ticket types	Adults, Kids, Seniors	All visitors
Traffic survey	Cars, Bikes, Trucks	All vehicles

Tally counter for multiple things at once