<p>The textile industry increasingly seeks eco-friendly alternatives to conventional dyeing, which often relies on synthetic dyes and toxic metallic mordants. While synthetic dyes offer vibrant, durable colors, they raise serious environmental concerns. Natural dyes, though biodegradable, typically require mordants for effective fiber binding. This review investigates the chemical principles and environmental implications of natural and synthetic dyes used with metal mordants in textile applications. Key challenges include the toxicity of traditional mordants like chromium and copper, and the limited fastness of natural dyes. The study compares the dye performance of mordanted versus non-mordanted fabrics and reports that mordanted textiles exhibit up to 2 × higher color strength (K/S values) and significantly better wash and light fastness. Recent advances in computational modeling, including density functional theory (DFT) and molecular docking, provide insight into dye-mordant interactions, guiding the rational design of more effective and environmentally friendly systems. Moreover, bio-mordants—derived from tannins and plant extracts—demonstrate potential as renewable, non-toxic alternatives. This review underscores the urgent need for sustainable dyeing strategies that reduce ecological impact without compromising performance. By integrating experimental chemistry, green alternatives, and computational tools, it presents a multidisciplinary framework for optimizing mordanting practices in future textile production.</p> Graphical Abstract <p></p>