# Modelling tools
###### tags: `ISTQB` `SQA` `Test tools`
**Modelling tools are used primarily by developers during the analysis and design stages** of the development life cycle. ==The reason modelling tools are included here is because they are very cost-effective at finding defects early in the development life cycle.==

Their benefits are similar to those obtained from the use of reviews and inspections, **in that modelling tools allow omissions and inconsistencies to be identified and fixed early** so that detailed design and programming can begin from a consistent and robust model.

This in turn prevents fault multiplication that can occur if developers build from the wrong model.

**Benefit**
For instance, a visual modelling tool using UML can be used by designers to build a model of the software specification.
==The tool can map business processes to the system architecture model==, which, in turn, **enables programmers and testers to have a better and common understanding of what programs should do and what testing is required.**

Similarly, the use of database, state or object models can help to identify what testing is required and can assist in checking whether tests cover all necessary transactions.