[MGO, UMF and KFactor explained]

Manuka honey is measured with a collection of unique Manuka Honey rating systems, but before we can break down the grading system, we need to understand exactly what they are measuring.

There are several components to Manuka Honey:


The most well known component of manuka is MGO, or methylglyoxal. Don’t sweat the fancy name – it’s simply a compound that’s been measured to have very strong antibacterial properties (study here, if you’re interested).


The second unique ingredient of Manuka Honey is DHA or dihydroxyacetone, is also essential in a good manuka. The production of MGO is dependent on high DHA levels in the manuka flower, and therefore a high DHA level is usually a precursor of high levels of MGO.


The third unique ingredient of Manuka Honey is NPA or non-peroxide activity, and is what brings it all together. NPA is important because many of the proven benefits of manuka honey is dependent on the presence of NPA.

Potency of the honey is highly dependent on this. Check this carefully in any manuka honey you buy: Honeys with low or no NPA are generally considered low quality Manuka Honey, and honeys with high levels of NPA are considered high quality Manuka Honey. 


Leptosperin is the final piece of the Manuka Honey puzzle. It's a chemical found only in the nectar of Manuka plants.

This is often used as a marker to determine if Manuka Honey is genuine. If leptosperin is unable to be found, it is unlikely the honey is authentic Manuka.

The above four compounds are what determine the quality of a good Manuka Honey, and are used to determine a Manuka Honey rating. Of course there are other measurements you can make, but the ones above are unique to Manuka Honey and the most important to look for.

manuka honey grades explained:


wild capes manuka honey umf

What is UMF?

UMF stands for Unique Manuka Factor.

This is a grading system developed by the UMF Honey Association in New Zealand, where the manuka plant originates from. The highest quality manuka honey in the world comes from New Zealand’s shores, and many of the top honeys out of the country grade their honey using the Manuka Honey UMF system.

NPA, or non-peroxide acitivity, is central to the UMF grading system. As we said earlier, the potency of any manuka honey is highly correlated with NPA. Without NPA, the honey is simply considered poor quality. The actual UMF grade on the honey jar itself corresponds directly to the NPA. Therefore if the NPA level is 15, the honey will be marked “UMF 15”.

UMF also measures DHA and MGO levels, to determine sufficient levels of antibacterial activity, plus the presence of leptosperin to ensure honey has been produced from real manuka flowers.

The final part of UMF grading is a test for HMF or Hydroxymethylfurfural. HMF concentrations increase under excessive heat and prolonged storage times. In some cases, heat can be used to accelerate the conversion of DHA to MGO fraudulently. To secure a UMF rating, the HMF content after processing should not be more than 40 milligrams per kilogram to ensure the levels of MGO and DHA has not been manipulated by heating.

There is no official highest UMF rating for Manuka Honey, but it is rare to see Manuka Honey achieve a rating above 30, at least for consumer use.

UMF is the most comprehensive manuka honey grading system in place today and considered the best indicator of overall antibacterial quality. If you are looking for UMF certified Manuka Honey brands, you can see all current members of the UMFHA here.



comvita manuka honey mgo rating

The Manuka Honey MGO grading system is less complex than UMF, and only measures the level of MGO.

What is MGO? 

MGO is an abbreviation for Methylglyoxal, which is the naturally occurring compound that comes as a result of DHA in the Manuka flower. MGO contributes largely to Manuka's Honey's antibacterial mechanisms.

The MGO number tells you how much MGO is present in the jar of honey, so the higher the MGO rating, the higher the grade of honey.

There are two things to be aware of with MGO gradings: 

One, the level of MGO can change over time, so the amount of MGO in your honey when it was packed and the level when you buy and consume it may be different.

Second, MGO is also not solely responsible for Manuka Honey’s antibacterial properties – there are other compounds that contribute to how potent a particular manuka is. Therefore when it comes to UMF vs MGO, MGO is less reliable than a UMF grading, but can still be somewhat helpful in determining quality.

The MGO grading system was pioneered by Manuka Health in 2008.


k factor wedderspoon manuka honey

Manuka Honey KFactor is a grading system invented by the company Wedderspoon.

The system is based on five key factors that Wedderspoon has chosen, based on New Zealand's agricultural ministry standards. They are:

  1. Raw and unpasteurized
  2. Non GMO verified
  3. Produced and packaged in New Zealand
  4. Free of glyphosate pesticides and antibiotics
  5. Traceability from Hive to Home
wedderspoon kfactor

KFactor comes with two gradings: Kfactor 16 and KFactor 12, although the numbers are insignificant and they could just as easily have been called KFactor 1 and KFactor 2. 

KFactor16 is Wedderspoon's monofloral Manuka Honey, meaning the honey is wholly made from the Manuka flowers.

KFactor12 is Wedderspoon's multifloral Manuka Honey, meaning the honey is a blend of Manuka flower pollen and other pollens as well. In other words, it's not a pure Manuka Honey but a Manuka and non-Manuka blend.

The main criticism of the KFactor system is that it doesnt test the most important components of Manuka Honey, those being NPA, MGO, DHA or leptosperin levels.

No company other than Wedderspoon has adopted this rating system as of yet.

Comparing manuka honey grading systems

We generally recommend Manuka Honey buyers to stick with UMF certified brands, as it is the most reliable grading system. MGO and KFactor are less thorough, and do not require certification from the UMF Association. 

However, it can be helpful to compare grades as this makes it easier to compare products. The table below will give you a (loose) comparison between UMF gradings, MGO gradings and KFactor scores.





Similar or indistinguishable from regular honey




Medium level honey. Good for general wellbeing.




Good quality honey with significant antibacterial activity.




High quality honey with high antibacterial activity.




Ultra quality honey with medicinal antibacterial activity.




If you are looking to purchase Manuka Honey, we recommend checking out our list of recommended brands.