Weibull distribution calculator
Calculate probabilities and quantiles for a positive lifetime with shape k and scale λ.
How do I use this page?
- Choose density, CDF, survival or quantile.
- Enter positive k and λ.
- Provide x or probability q and read the result.
What this page does not do: Interpreting k as a failure pattern requires time-to-event data and treatment of censoring. This calculator evaluates a distribution; it does not fit parameters to data.
Further reading
Theory — what is the Weibull distribution?
The Weibull distribution models positive lifetimes and is widely used in reliability analysis. The scale parameter λ stretches the time axis, while the shape parameter k changes how the hazard rate behaves over time — when k=1 the distribution reduces to the exponential distribution. The calculator computes probabilities and quantiles for the given k and λ. It is worth remembering that at x=λ the CDF always equals about 63.2%, regardless of the shape parameter.
Frequently asked questions
What does λ mean?
Does this calculator estimate parameters?
See also
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