Used as a pH indicator in acid-base titrations and laboratory analyses. Employed in the Methyl Red (MR) test for identifying and differentiating microorganisms in microbiology. Utilized in research and educational laboratories for pH determination. Used in certain analytical procedures requiring visual detection of pH changes.

Its primary purpose is to indicate changes in acidity or alkalinity enabling accurate pH measurement and endpoint detection in chemical and microbiological analyses.

Methyl red is an azo dye commonly used as a pH indicator in analytical chemistry. It appears red in acidic solutions and yellow in alkaline solutions with a color transition range of approximately pH 4.46.2.