What Does USP Grade Mean? USP vs. Lab vs. Technical Grade
You'll see "USP grade" on a lot of product labels, including ours. But what does it actually mean, and how is it different from "lab grade" or "technical grade"? Here's a plain-English guide to chemical grades and what to look for when you buy.
What is the USP?
The United States Pharmacopeia (USP) is an independent, nonprofit organization founded in 1820. It publishes the USP–NF, a compendium of public quality standards for medicines, ingredients and related materials. Each ingredient has a written standard, called a monograph, that defines its identity, strength, quality and purity, along with the test methods used to check them.
What does "USP grade" mean?
An ingredient labeled USP grade meets the requirements of its USP monograph. In practice, that means it has been tested against defined limits for identity, purity and specific impurities using recognized methods.
One important note: "USP grade" describes the material's quality standard. It is not the same as the USP Verified mark, which is a separate program, and it does not mean the USP has reviewed or endorsed a particular product or company.
Common chemical grades compared
| Grade | What it generally means |
|---|---|
| ACS / Reagent | Very high purity that meets American Chemical Society specifications. Typically used for analytical lab work. |
| USP | Meets the identity, quality and purity requirements of its United States Pharmacopeia monograph. |
| NF | Meets National Formulary standards, the companion to the USP for many excipients and inactive ingredients. |
| Laboratory | Reasonably pure, but impurity levels often aren't fully specified. Suited to education and general lab use. |
| Technical / Industrial | Intended for industrial or commercial applications. Purity and impurity limits are less strict. |
Grades aren't a strict ladder, and exact requirements depend on the specific material. The key difference is how well defined, and how tightly controlled, the purity and impurity limits are.
What to check before you buy
- A lot number on the bottle. This ties your product to a specific tested batch.
- A Certificate of Analysis (COA). Look for one that matches your lot number and shows results against specifications. Our guide on how to read a COA walks you through it.
- An expiration or retest date.
- Clear sourcing information. Know who made the material and where it was packaged.
USP grade at Compass Laboratory
Our Methylene Blue 1% and Methylene Blue 0.5% are made with USP-grade methylene blue and reverse osmosis water, and are manufactured and bottled at our facility in Mena, Arkansas. Our propylene glycol and vegetable glycerin are sourced in bulk as USP-grade material from a certified supplier and repackaged at the same facility.
Every bottle carries a lot number and expiration date, and you can find the matching COA on our Our Standards & Certificates of Analysis page.
This article is for general educational purposes only.