Grading System Explained

Grading System Explained

Mānuka Honey is highly valued by the consumer and those that are licensed to use the quality mark. The UMF quality mark is registered in all key consumer markets.

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UMF Grading System

The UMF grading system has two components which are expressed on any UMF honey product



The label claim that it is genuine Mānuka Honey.



This represents the unique signature compounds characteristic of this honey which ensure purity and quality. These include: the key markers of Leptosperin, DHA and Methylglyoxal.

Antibacterial Activity Explained - MGO/NPA Mānuka honey conversion calculator

All honey has antibacterial activity due to what is commonly called Peroxide Activity (PA). However, Mānuka Honey has a special, unique antibacterial activity called Non-Peroxide activity (NPA).

  • People are often interested in the anti-bacterial activity of Mānuka honey.
  • Research has shown that NPA is very stable in Mānuka Honey even when it is exposed to light and heat.
  • We know that there is a direct relationship between NPA (antibacterial activity) and the level of Methylglyoxal (MGO) which is a key signature marker found in Mānuka honey. However, while there is a relationship between the two, MGO is not the sole cause of NPA in Mānuka Honey..

The calculator below has been specially designed to help you understand that relationship.

The UMFHA has developed internationally recognized testing procedures to confirm the presence of key signature markers – MGO, Leptosperin and DHA – found in genuine, pure, quality Mānuka honey from New Zealand.


Methylglyoxal to NPA
NPA to Methylglyoxal

Enter Methylglyoxal value to convert:

Mg must be less than 2450 ppm


Corrigendum to 'Isolation by HPLC and characterization of the bioactive fraction of New Zealand manuka (Leptospermum scoparium) honey' [Carbohydr. Res. 343 (2008) 651]. Christopher. J. Adams, Cherie H. Boult, Benjamin J. Deadman, Judie M. Farr, Megan N. C. Grainger, Merilyn Manley-Harris *, Melanie J. Snow

UMF Grades

Hover over chart to display precise values