OpenGUTS is a user-friendly software to perform analyses with GUTS: the General Unified Threshold model for Survival. GUTS is the leading toxicokinetic-toxicodynamic framework for the endpoint survival (and other non-reversible all-or-nothing effects). 

This site hosts the software itself, as a standalone Windows executable, with manuals and background documentation. Since openGUTS is (as the name implies) open source, also the source files can be obtained here. Additionally, you can download the Matlab version, which served as the blueprint for the standalone version. The Matlab version has basically the same functionality, and can be easily adapted or extended to perform customised analyses. Finally, we provide (links to) further information on openGUTS and GUTS. The main features of the software are:

1. Open and free: the software is open source and freely downloadable. The fully-functional Matlab version that served as the prototype is also available.
2. User-friendly: fit models and derive confidence intervals without requiring user interaction (e.g., no need for starting values).
3. Robust: always find the global optimum and relevant intervals, even for awkward data sets.
4. Flexible: allow time-varying exposure, missing data, simultaneous fitting on multiple data sets, etc.
5. Efficient: rapid screening of exposure profiles (e.g., FOCUS output) by batch processing.
6. Supportive: the software follows the workflow as laid down in the 2018 EFSA opinion on TKTD models.