Tools in your browser
Free tools for survival analysis, study design, and health-economic modelling — each runs entirely in your browser, nothing uploaded and nothing installed. Set the inputs, watch the curves update live, and export run-ready R or Stata code when you want to take it further.
Built by the team behind the merlin family, each tool doubles as a live demonstration of the methods we develop, teach, and consult on.
Grouped by what you need to do
Each one opens in a new tab, runs entirely in your browser, and exports to our R and Stata packages.
Understand
Move something and watch what it does.
2
Estimands
When the hazard ratio misleads
One hazard ratio for the whole of follow-up. Watch it hide a delayed, waning or crossing effect, and see what RMST and milestone survival say instead.
Open tool →
Multi-state
Multi-state & competing-risks explorer
Set the states and the transitions between them, and see where patients actually end up — illness–death, competing risks and progression models, with length of stay.
Open tool →Plan
Work out what the study needs, before you have data.
2
Power
Sample size & power calculator
How many patients you need for the effect you expect to find, and what you can detect with the ones you have — means, proportions, log-rank and Cox.
Open tool →
Survival
Survival DGM explorer
Choose the data-generating mechanism your simulation study will assume, before it assumes one for you — standard families, splines, and time-dependent effects.
Open tool →Specify
Turn the decision into code you can run.
2
Model choice
Which model do I need?
Answer a few questions about the shape of your data and leave with a named model, the command in R and Stata, and a tutorial that works it end to end — or a plain statement that your design needs a conversation, not a default.
Open tool →
Model specification
Build a merlin model
Pick the baseline hazard, the clustering and the extensions, and leave with the syntax in both languages — together with what you have just assumed, and what to check before you trust it.
Open tool →Deliver
Produce something you can put in a submission.
2
Survival
Reconstruct & extrapolate a KM curve
Turn a published Kaplan–Meier curve back into patient data, then extrapolate it out to a lifetime horizon — the survival-extrapolation problem at the heart of health technology assessment.
Open tool →
Partitioned survival
Partitioned survival analysis explorer
Progression-free and overall survival in; state occupancy, QALYs, ICER and a cost-effectiveness plane out — including the curve-crossing pitfall, and export to merlin or pendragon.
Open tool →