The Mexican Standards, commonly called NMX, should not be confused with the Mexican Regulations or the Official Mexican Standards (NOM). According to the Federal Law on Metrology and Standardization of Mexico[1]​ (LFMN), Mexican Standards are the regulations of voluntary application prepared by a National Standardization Organization, or the Ministry of Economy in their absence.

The Mexican Standards provide for common and repeated use rules, specifications, attributes test methods, guidelines, characteristics or prescriptions applicable to a product, process, installation, system, activity, service or method of production or operation, as well as those related to terminology, symbology, marked or labeled packaging and their specifications must not be lower than those contained in an Official Mexican Standard.

Products and services that comply with Mexican Standards can use the "Official Password" or NMX seal, which is regulated by the Official Mexican Standard NOM-106-SCFI-2017.[2]​.

In Mexico, Mexican Standards can be issued by private entities known as National Standardization Organizations (ONN); the above in terms of what is indicated in the Federal Law on Metrology and Standardization. Currently, the National Standardization Organizations that can issue Mexican Standards are:

De acuerdo con lo establecido en la Ley Federal sobre Metrología y Normalización de México,[1]​ las Normas Mexicanas pueden ser expedidas por los Comités Técnicos de Normalización Nacional (CTNN) que al efecto cree la Secretaría de Economía; In this sense, until 2017[3]​ the following committees existed:

When Mexican Standards are issued, they have in their identification code a letter that corresponds to their branch or industrial sector,[4]​ Currently, the industrial branches for Mexican standards are:

The list of Mexican Standards can be consulted on the page of the Comprehensive System of Standardization and Conformity Evaluation SINEC).[5]​ of the Ministry of Economy.