After Poisson distribution and Triangular distribution calculators, jamais deux sans trois, I decided to give Normal distribution a run. Certainly it is the most important distribution of all.

So here you go. Click image to go to the interactive version.

Note there two ways to calculate, given the same mean and stdev:
1.enter the parameter in the box X.
2.mouse over X.

It seems there is no such a calculator for TriAngular Distribution on the web. So I created one.

There are 4 parameters:
Min,
Mode,
Max
and Bin Size.
Change the parameters according to your need.
Click image to view the interactive version.

Poisson distribution is so important that I had to learn it in a recent project. Learnt to use it to be exact.

Thus came an idea to visualize it in Tableau, because I couldn't find a good visual reference on the web about it.

Here you go. It shows two charts:
1.Probability distribution per K (the number of occurrences).
2.Cumulative probability for all events where the number of occurrences <=K.
3.Both λ and the range of K are in parameters.
Click image to view the interactive version.

You might notice that we need to calculate the factorials of K in Poisson distribution. The initial calculation formula failed because the numbers were too big for integer operations. A workaround is found using floating point calculations.

[Update]Added an alternative view that highlights the complementary property of <=K and >K probabilities:
Click image to view the interactive version.