UMF™ vs MGO vs KFactor vs BioActive vs MGS vs NPA? Who’s confused about Manuka Honey?

Manuka Honey is a complex and high strength raw honey that is produced when worker bees gather nectar from the flowers of the native New Zealand Manuka tree. Extensive international research has been carried out on New Zealand Manuka Honey, specifically centred around its health benefits and high levels of naturally occurring energy and strength. It is the high methylglyoxal levels in the Manuka Honey that makes it so sought after.

The most common Manuka Honey independent grading systems seen on labels include:

  • UMF (Unique Manuka Factor)
  • MGS (Molan Gold Standard)
  • K-Factor
  • Bio Active

Other numbers seen on labels that are understood to be grading systems are below. These are in fact, not grading systems but measurements of markers in the honey. Including:

  • MGO (Methylglyoxal)
  • NPA

What do UMF, MGO, BioActive, MGS, KFactor and NPA test and measure?

The following list outlines the different Manuka grading systems and what each measure, as per what is published and publicly available. For more understanding on each testing marker and what they mean continue reading below.

UMF Manuka Honey Grading LogoUMF

UMF is the standard of measure used by the UMFHA - Unique Manuka Factor Honey Association. The UMFHA is an independent body established in New Zealand in 1998 to test, control and protect New Zealand's Manuka Honey industry. A UMF grading test measures Leptosperin, MGO (Methylglyoxal) DHA and HMF. It is the only grading system that measures all four chemical markers and is considered the strictest and highest graded Manuka Honey measurement system.

A benefit to you, the consumer, is that UMF is 100% transparent about what it tests and measures and those measurements are available and displayed.

A company producing and selling UMF Manuka Honey must be licensed by the UMFHA to sell Manuka Honey that is UMF rated. It is also a requirement to have the UMF logo AND grading number on a label. Searching for a companies licence number can be done via the UMF website:

The UMF Honey Association is the only known grading standard where the governing organisation carries out independent testing of its members honey once it reaches retail and online stores globally, thus ensuring authenticity.

No other grading system independently performs these authenticity tests which ensure the honey has not been tampered with since export, and that it maintains it’s quality levels. UMF honey is guaranteed to hold, at a minimum, the strength as stated on the label e.g. UMF 15+,  for its shelf life.

A sample testing certificate from our New Zealand Honey Co. Honey can be seen below clearly indicating the specific Manuka Honey markers that are tested for over and above the MPI requirements. This testing is done by an independent testing facility approved by the MPI to conduct Manuka Honey testing.

Manuka Honey UMF Certificate - Analytica Laboratories


Bio Active measures both the peroxide and non-peroxide activity of Manuka Honey. This can be difficult to measure accurately as the hydrogen peroxide (H202) antibacterial activity degrades very quickly when exposed to fluids, heat and sunlight. Bio Active has recently given way to MGO as the preferred grading system.


MGS measures MGO and DHA levels in Manuka Honey between 5+ and 30+ and the number assigned correlates to the equivalent phenol strength of the Manuka honey antibacterial activity. MGS will not provide a grade for Manuka honey which has MGO levels of less than 100 mg/kg.


KFactor does not reportedly measure MGO, NPA or Leptosperin levels. In early marketing materials it reportedly measured and reflected pollen count but this seems to no longer be promoted. KFactor focuses on 5 general pillars unrelated to the specific activity levels in the honey.

Non-grading measurements


MG, or MGO measures the methylglyoxal level in Manuka Honey. MGO is the strength and energy within Manuka Honey and is what makes it effective for health and wellbeing.

MGO is not a technical grading system. It is a measure of the MG (methylglyoxal) level in the Honey.


NPA is the non-peroxide activity, which is the additional antibacterial activity found in Manuka Honey. It is calculated from the concentration of MGO and it corresponds with the UMF equivalent grade of honey eg. 5+, 10+, 15+.

While this is also not an established grading system it is mentioned as countries including the UK most commonly understand the NPA value.

UMF & MGO & NPA Chart

MGO Levels
NPA Levels


Checklist to Identify Genuine UMF™ Manuka Honey

Genuine UMF Manuka Honey must comply with the following criteria:

  1. The quality UMF trademark is clearly stated on the label.
  2. The honey is produced in New Zealand. As mentioned above, honey cannot be imported into New Zealand. The consumer is assured that UMF Manuka honey is truly and only New Zealand Manuka Honey.
  3. It is processed, packed and labelled in New Zealand.
  4. It has the New Zealand UMF Licensee’s brand name on the label (and is also present on the UMFHA website licensees list
  5. It is produced by a New Zealand company licensed to use the quality trademark UMF.
  6. A grading number without the abbreviation UMF does not identify genuine UMF Manuka Honey. It must have a rating number alongside the trademark UMF.
  7. It can be verified by the Official UMF Release Document which states the test results for the batch number shown on the jar label. The Official UMF Release Document presents test results for all four Manuka markers (Leptosperin + Methylglyoxal + DHA + HMF)


Manuka Honey Grading & Production

Each Manuka Honey grading system used on the packaging is shown in the form of numbers and letters. It can be confusing to know what each grading system indicates and what the numbers mean.

Common grading systems we've listed include UMF, MGS, KFactor and BioActive. But what does each chemical marker in the honey mean and how can you have confidence when purchasing honey labelled as New Zealand Manuka Honey? In this section, we aim to clarify and demystify the terms and information that surround each Manuka Honey grading system.

The information below is updated as often as possible to reflect the latest standards from each grading system.

In brief, the common process for Manuka Honey production, testing and exporting is as follows. It's important to understand the process of Manuka Honey production and how it is prepared before export:

  1. Manuka Honey is collected from hives in New Zealand
  2. Manuka Honey is extracted from the hives and samples are sent to independent laboratories for MPI testing to identify if it is a monofloral or multifloral Manuka Honey (UMFHA association members have additional testing done for UMF grading. See Analytica 3-in-1 for more details).
  3. From the MPI test results, the honey is then identified as multifloral or monofloral Manuka Honey. 
  4. Honey is packaged and labelled in New Zealand and then exported (some companies export and then package & label overseas). At this point, companies will also place their specific grading numbers on the jar labels.
If a company is a member of the UMFHA additional testing may be performed once honey has been exported to ensure it’s authenticity after it reaches your shelves.

    Did you know?
    • It is illegal to import honey into New Zealand. It’s important to check that the Manuka honey you’re considering purchasing has been processed, packed and labelled in New Zealand to ensure it is 100% authentic New Zealand Manuka Honey.
    • The Manuka plant is native to New Zealand
    • Mānuka is a Māori word used for the Leptospermum scoparium tree

    How do I know that it’s authentic New Zealand Manuka Honey I am purchasing?

    To protect the integrity of Manuka Honey, the New Zealand government has set strict regulations around how it is produced and sold to the public. The NZ Ministry of Primary Industries (MPI), a government organisation, clearly stipulates the legal requirements regarding the export of Manuka Honey. This includes a scientific test of 4 chemical markers and a single DNA marker in the honey. For a monofloral Manuka Honey the test requirements are as follows:

    Test 1: Chemical test

    The following chemicals all need to be present and at these levels:

    • 3-phenyllactic acid at a level greater than or equal to 400mg/kg
    • 2’-methoxyacetophenone at a level greater than or equal to 5mg/kg
    • 2-methoxybenzoic acid at a level greater than or equal to 1mg/kg
    • 4-hydroxyphenyllactic acid at a level greater than or equal to 1mg/kg

    Test 2: DNA test

    • DNA level from Manuka pollen is less than Cq 36, which is approximately 3fg/µL.

    This means regardless of the proprietary grading system used on the label, a Manuka Honey must first pass the minimum testing requirements set out by the MPI. 

    The results of the MPI test also indicate whether the Manuka Honey is classified as a multifloral or monofloral honey. This must also be clearly stated on the label. A monofloral Manuka Honey is typically labelled as ‘Manuka Honey’ and is considered of higher strength due to it’s higher Manuka concentrations. A multifloral Manuka Honey must also be labelled as such, often called ‘Manuka Blend’, 'Multifloral Manuka' or ‘Manuka Honey Blend’ on labels.


    What is a monofloral Manuka Honey?

    Monofloral Honey is honey that comes from the nectar of one main flower. In the case of Manuka Honey, this is the Manuka flower.

    What is a multifloral Manuka Honey?

    Multifloral honey is honey that comes from the nectar of many flowers or honey that has been blended with other honey. If the Manuka levels in honey are not sufficiently high, a Manuka Honey will then be labelled as a multifloral Manuka Honey.

    Watch our Head Beekeeper explain more about multifloral and monofloral Manuka Honey here. 

    The initial MPI testing required can be considered the minimum requirement for a company to begin exporting honey labelled as Manuka Honey from New Zealand.

    All New Zealand Honey Co. Manuka honey is independently laboratory tested to ensure it meets or exceeds the required MPI levels to export pure raw Manuka Honey.

    These MPI tests give you the confidence you are buying authentic NZ Manuka Honey but it does not tell you the strength in the honey. This is an important measure and is a reason Manuka Honey is so highly sought after. For the additional quality measurements, further testing is needed to identify the markers relating to the Manuka Honey’s potency and authenticity.

    It is important to note that once the honey has been exported from NZ there are no further measures or requirements from the MPI to guarantee the authenticity of the honey on the shelf. This can create a gap between the export process and the honey arriving on your table. Honey labelled with a UMF grade provides assurances around this which we will explain in more detail below; essentially the UMFHA continue to test honey on shelves around the world to ensure it is delivered to you unadulterated.

    Once a Manuka Honey has passed MPI testing and is cleared for export, the additional independent grading systems are applied to Manuka Honey Labels by each producer - UMF, BioActive, MGS, KFactor; some also print the MGO levels for reference.

    Typically each grading system has a numeric element to it e.g. UMF 15+, KFactor 16 etc.  These are the additional numbers you will see on the honey jars promoting the quality and health properties of the honey. MGO numbers can be seen typically from MGO 83+ to MGO 1000+.

    A widely accepted and comprehensive grading system is UMF™ (Unique Manuka Factor) which is overseen by the UMFHA (Unique Manuka Factor Honey Association) in New Zealand. This is an independent body with over 100 NZ Manuka Honey exporters as members.

    What can be tested for in Manuka Honey?

    It is important with each of the Manuka grading systems that we understand what can be tested for in Manuka Honey. These different ‘markers’ exist in Manuka Honey which, when tested, provide evidence of the honey’s authenticity and antibacterial levels.

    The desirable elements of NZ Manuka Honey, including being free of additives, no GMOs and unpasteurised, should be expected. As an example, our New Zealand Honey Co. honey is principally sourced from remote New Zealand mountains where no sprays are used on the farmland. To date, GMOs are not present (no fresh produce (fruit, vegetables, meat or milk) originating in New Zealand is genetically modified) and the wild NZ landscape results in organic honey by nature. It is antibiotic-free, no additives are present and it is unpasteurised (some companies heat their honey to levels equalling pasteurisation - UMF labelled honey, like New Zealand Honey Co. Manuka Honey, is not heated and HMF testing supports this).

    The following scientifically tested markers provide you, the consumer, confidence in your Manuka Honey purchase. You will see these markers clearly indicated in the sample UMF Manuka Honey testing report further below.

    • Testing for Leptosperin is the best way to identify genuine Manuka honey as it is specifically present in the nectar of the Manuka flower. It provides evidence that the honey tested derives from the Manuka plant (Leptospermum scoparium)
      MG / MGO
      • MGO is the measurement of Methylglyoxal in Manuka Honey. The higher the MGO level, the more effective the Manuka Honey is.
        • Along with Leptosperin, Dihydroxyacetone (DHA), is also present in the nectar of the Manuka flower. The maximum concentration of MGO in the Manuka Honey can be determined by its DHA concentration.
          • Non-Peroxide Activity that is essentially additional antibacterial activity found in Manuka Honey and is calculated from the concentration of MGO. It corresponds with the UMF™ equivalent grade of honey eg. 5+, 10+, 15+.

          These are the four commonly acknowledged key markers that identify the quality of the Manuka Honey you are purchasing.

          A separate marker called HMF can also be tested. This test ensures the honey you are buying has not been modified to create an intensified MGO reading.

          • Hydroxymethylfurfural (HMF) indicates whether honey has been heat treated or aged. Reasons for heat treating and ageing Manuka honey are to quickly increase the level of MGO content to make it more valuable commercially.

          Our head beekeeper talks through what to look for when purchasing Manuka Honey.


          Check out some of our other articles to educate yourself more on Manuka Honey:



          Different Manuka Honey Grading Systems - UMF vs MGO vs BioActive vs KFactor vs MGO


          One of the best Manuka Honey articles I’ve read! Thank you 🙂


          very well written post.

          S G

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