Triangular Distribution Calculator

About this calculator

The triangular distribution is a simple continuous probability distribution defined by just three numbers: a minimum a, a maximum b, and a most-likely value (mode) c, forming a triangle-shaped probability density that peaks at c. This calculator evaluates that distribution at any point x, returning the probability density (PDF) at x, the cumulative probability (CDF) of a value falling at or below x, and the distribution's overall mean, (a+b+c)/3.

Because it needs no historical data — only a best guess, worst case and most likely estimate — the triangular distribution is a go-to tool in project management, risk analysis and Monte Carlo simulation, especially in PERT-style estimating where a task's duration or cost is bounded by optimistic, pessimistic and most-likely figures supplied by subject-matter experts. Statistics students also meet it as an accessible first example of a non-uniform continuous distribution before moving on to more complex bell-shaped curves.