Acetylcholinesterase (AChE) is an important enzyme and target for human therapeutics, environmental safety and global food supply. Adverse effects of AChE pesticides on non-target organisms, such as fish, amphibians and humans, have also occurred as a result of biomagnifications of these toxic compounds. We have exhaustively curated the public data for AChE inhibition data and developed machine learning models for seven different species. MegaAChE enables the user to predict the AChE inhibition of molecules across all these models to enable prioritization for testing.