How to use this tool
- Enter shape, scale, value x.
- Select Calculate to view the result.
- Check the method and assumptions below before using the result.
The method, explained
CDF = 1−Q(shape,x/scale), using the regularized upper incomplete gamma Q.
Using shape = 2, scale = 1, value x = 2, the result is 0.59399415. Change these example inputs to match your task; use the method above to check each step.
Understanding your result
Scale parameterization, not rate. Main result is P(X≤x); rate is the reciprocal of scale.
What to keep in mind
Scale parameterization, not rate. Main result is P(X≤x); rate is the reciprocal of scale. A descriptive or probability calculation under the stated assumptions. Check the sample design and model before interpreting results.
Common questions
How do I use this gamma distribution calculator?
Evaluate a gamma cumulative probability using shape and scale parameters. Enter shape, scale, value x. The starting example is editable; use values for the same system or project.
Which assumptions affect this result?
Scale parameterization, not rate. Main result is P(X≤x); rate is the reciprocal of scale.
Methodology maintained by ClarityKit. How these tools are built and checked.