> For the complete documentation index, see [llms.txt](https://help.arkance-systems.com/pressure-drops/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.arkance-systems.com/pressure-drops/en/general/installation-and-activation/trial-activation.md).

# Trial Version Activation

Pressure Drops is licensed with a license key. To get a trial key, click the Try it for free button. Fill in your initials and email address here. You will then receive a trial key, which you insert into the relevant field of the license window and activate the trial license.