<p><i>Amaranthus tricolor</i> is an underutilized pseudocereal that can grow in various climatic and stress conditions. It has medicinal properties such as antioxidant, anti-inflammatory, antidepressant, and hypoglycaemic. Microgreens are tender immature greens that are loaded with nutrients. This study investigated the growth-related parameters, bioactive compounds, and antioxidant activity of two varieties of <i>A. tricolor</i> (Pusa Lal Chaulai and Pusa Kiran) microgreens grown in cocopeat. They were harvested on fifth, tenth, and fifteenth days post germination (dpg) and their methanolic extracts were analyzed. Tenth dpg microgreens of both varieties had the highest total phenolic content (TPC), total flavonoid content (TFC), and total terpenoid content (TTC). Similar results were observed for antioxidant activity where tenth dpg microgreens of both the varieties have the least 50% inhibitory concentration (IC₅₀) in DPPH and ABTS radical scavenging assay and the highest FRAP reducing potential. Volatile metabolites were determined for methanolic extracts of both varieties of tenth dpg microgreens using gas chromatography and mass spectrometry (GC–MS). The presence of compounds such as chondrillasterol, n-hexadecanoic acid, neophytadiene, phytol, tocopherol, and squalene in microgreens of <i>A. tricolor</i> makes them nutritionally rich. Additionally, they exhibited promising antioxidant properties. Thus, they may be explored further for nutraceutical potential and the development of dietary supplements.</p> Graphical abstract <p></p>