AGGRESCAN is a web-based tool for predicting and evaluating "hot spots" of aggregation in polypeptides. It identifies aggregation-prone segments in protein sequences, analyzes the effect of mutations on aggregation propensities, and compares the aggregation properties of different proteins. The tool is based on an aggregation-propensity scale derived from in vivo experiments and assumes that short, specific sequence stretches modulate protein aggregation. AGGRESCAN identifies aggregation-prone segments in disease-related proteins and predicts the effect of mutations on their deposition propensities. It also provides insights into the differential aggregation properties of globular proteins, natively unfolded polypeptides, amyloidogenic proteins, and proteins in bacterial inclusion bodies. AGGRESCAN processes input polypeptide sequences and calculates aggregation-propensity values for each residue, along with graphical representations of the profile. It identifies putative aggregation "hot spots" and provides outputs such as tables, graphs, and normalized values. The tool can analyze large numbers of sequences simultaneously and is useful for comparing the aggregation properties of different protein sets. AGGRESCAN has been validated against experimental data and has successfully predicted aggregation-prone regions in various proteins, including Aβ42, synuclein, amylin, prion protein, transthyretin, β2-microglobulin, and lysozyme. It has also been used to analyze other proteins involved in amyloidosis and Alzheimer's disease, such as serum amyloid A and Tau proteins. The tool's predictions have been compared with experimental data and have shown good agreement. AGGRESCAN can predict the effects of mutations on aggregation propensities and has been used to analyze mutations in proteins such as Aβ42, Tau, and Stefin B. It has also been used to analyze the aggregation properties of proteins in bacterial inclusion bodies and to compare the aggregation properties of different protein groups, including globular, natively unstructured, and amyloidogenic proteins. AGGRESCAN is available as a web-based tool and is open-access. It is designed to facilitate the identification of therapeutic targets for antidepositional strategies in conformational diseases and to anticipate aggregation phenomena during the storage or production of bioactive polypeptides. The tool is useful for researchers in biotechnology and medicine and can be used to design strategies for the treatment of amyloidogenesis by targeting aggregation-prone regions in polypeptide chains.AGGRESCAN is a web-based tool for predicting and evaluating "hot spots" of aggregation in polypeptides. It identifies aggregation-prone segments in protein sequences, analyzes the effect of mutations on aggregation propensities, and compares the aggregation properties of different proteins. The tool is based on an aggregation-propensity scale derived from in vivo experiments and assumes that short, specific sequence stretches modulate protein aggregation. AGGRESCAN identifies aggregation-prone segments in disease-related proteins and predicts the effect of mutations on their deposition propensities. It also provides insights into the differential aggregation properties of globular proteins, natively unfolded polypeptides, amyloidogenic proteins, and proteins in bacterial inclusion bodies. AGGRESCAN processes input polypeptide sequences and calculates aggregation-propensity values for each residue, along with graphical representations of the profile. It identifies putative aggregation "hot spots" and provides outputs such as tables, graphs, and normalized values. The tool can analyze large numbers of sequences simultaneously and is useful for comparing the aggregation properties of different protein sets. AGGRESCAN has been validated against experimental data and has successfully predicted aggregation-prone regions in various proteins, including Aβ42, synuclein, amylin, prion protein, transthyretin, β2-microglobulin, and lysozyme. It has also been used to analyze other proteins involved in amyloidosis and Alzheimer's disease, such as serum amyloid A and Tau proteins. The tool's predictions have been compared with experimental data and have shown good agreement. AGGRESCAN can predict the effects of mutations on aggregation propensities and has been used to analyze mutations in proteins such as Aβ42, Tau, and Stefin B. It has also been used to analyze the aggregation properties of proteins in bacterial inclusion bodies and to compare the aggregation properties of different protein groups, including globular, natively unstructured, and amyloidogenic proteins. AGGRESCAN is available as a web-based tool and is open-access. It is designed to facilitate the identification of therapeutic targets for antidepositional strategies in conformational diseases and to anticipate aggregation phenomena during the storage or production of bioactive polypeptides. The tool is useful for researchers in biotechnology and medicine and can be used to design strategies for the treatment of amyloidogenesis by targeting aggregation-prone regions in polypeptide chains.