Abstract
This work provides a uniquely comprehensive and comparative overview of chemical probe sources and targets. This will be maintained and expanded for experts and non-informaticions seeking chemical probes to use in their work. We have analysed 944 experimental and 3,670 calculated probe candidates. Together these have evidence of specific binding for 796 human proteins across the target classes. We have flagged unsuitable (i.e. potentially misleading and resource-wasting) compounds from both probe groups. Compared to ChEMBL approved drugs, probes tend to be larger and more complex structures.