Spirulina quality is assessed in laboratories for key parameters like protein content (≥60%), phycocyanin levels (≥15%), heavy metals (lead, mercury, arsenic), microbial contamination, and purity. The Certificate of Analysis (COA) from third-party labs ensures compliance with global standards like USDA Organic, EU Organic, GMP, and HACCP. A simple at-home test includes checking colour (deep green-blue) and smell (fresh, non-fishy). For commercial-grade quality assurance, regular lab testing and batch tracking are essential.