Kaplan-Meier Lifetime Workbench

How to use Kaplan-Meier Lifetime Workbench

At each distinct time, the risk set includes every observation not previously removed. Tied events are applied together before same-time censoring. The survival step multiplies by (at risk − events)/at risk; the table also retains censor counts and the first time survival reaches one half.

1. Enter lifetime json (time, event boolean).
2. Choose the stated convention and check the units and supported model.
3. Calculate, inspect the result, then copy or download it.

Good to know

• Exact-grid inputs are plain decimals with at most six places and magnitude≤1e9. Raw JSON number spelling is checked before conversion; decimal strings can preserve exact grid values. Exact rational intermediates are bounded to 8192 bits. 1–500 nonnegative lifetimes in one unit with boolean event flags. Right censoring only; no delayed entry, left/interval censoring, competing risks, confidence intervals or extrapolation. Independent noninformative censoring is an assumption, not a tested fact. Greenwood variance is unavailable when every remaining subject fails at a time. Intended for equipment/education, not clinical prognosis or medical decisions.
• Local calculation only; no input persistence or external lookup. Text/JSON is limited to 30000 characters and output to 1000000 characters. Numeric model inputs and precision/work limits are stated on this page. Approximate JSON numbers retain full stored values; exact arithmetic outputs retain decimal or fraction strings. Unsupported states fail explicitly.