"Grade" on a chemical label is really shorthand for purity level and intended use — understanding the three most common tiers helps you avoid over- or under-specifying for your application.
Technical Grade
Technical (or industrial) grade is the workhorse tier — pure enough for general industrial use, manufacturing and process chemistry, but not certified to the tighter impurity controls that food or laboratory-reagent grades require. This is the right choice, and the most cost-effective, for the large majority of industrial applications where the chemical isn't touching food or going into a precision analytical measurement.
Analytical Reagent (AR) / Laboratory Grade
AR grade is manufactured and tested to tight purity specifications suitable for analytical chemistry and laboratory use, where trace impurities could skew a measurement or a reaction result. It's generally more expensive than technical grade and is rarely necessary for production-scale industrial processes — reserve it for lab testing, quality-control work, and analytical applications specifically.
Food Grade
Food grade isn't necessarily "purer" than AR grade in every respect — it's certified against food-safety-relevant impurity limits (heavy metals, microbiological safety) specifically for direct or indirect food contact, which is a different set of controls than analytical precision. Never substitute technical or AR grade into a food application on the assumption that a "purer" or "lab-grade" product must be safe — food-grade certification is its own specific requirement. See our guide on FSSAI compliance for food-grade buyers.
Choosing the Right Grade
Match the grade to the actual requirement, not the highest grade available — technical grade for general industrial use, AR grade only for laboratory/analytical work, and food grade specifically and only where the product will contact food. Over-specifying wastes money; under-specifying can create a genuine compliance or quality problem.