N-Ethyl-m-toluidine is used in quantitative structure–activity relationship (QSAR) models that are developed for predicting acute toxicity to the fathead minnow (Pimephales promelas) and for classifying the genotoxicity of secondary and aromatic amines.

Dye intermediates. For the synthesis of organic dyes, such as the preparation of triphenylmethane acid dyes, azo acid dyes and fluorotriazine reactive dyes, polyester fiber yellow disperse dyes and cationic dyes suitable for acrylic fiber dyeing; Synthetic organic pigments, using ETLD as raw material, can produce monoazo and bisazo organic pigments. It can also be used to synthesize color developers.