Size exclusion chromatography (SEC) is currently the most powerful chromatography technique for obtaining reliable information about the size of biomolecules under native conditions. As such, it is widely used in several different analytical applications from basic research to quality control of biotherapeutics. This educational microsite, produced in collaboration with GE Healthcare, presents fundamentals about analytical SEC, tips to ensure successful analysis, available products and applications showcasing the role of SEC in biomolecule analysis.