UMF, MGO, KFactor, and More: Decoding Mānuka Honey Grading Systems
Two jars sit side by side. One says UMF 15+. One says MGO 514+. A third says KFactor 16, and a fourth just says “Active”. Are they the same honey at different prices, or different honeys entirely?
Mānuka is graded by several competing systems that measure different things. Here is what each one actually tells you.
MGO — a direct measurement
MGO states the concentration of methylglyoxal in milligrams per kilogram, confirmed by laboratory testing. MGO 700+ means at least 700mg per kilogram in that batch.
Its virtue is simplicity: one compound, one number, directly comparable between any two brands using it. Its limitation is that it measures only that compound — it is not, on its own, a test of whether the honey is genuinely mānuka.
UMF — a licensed composite
UMF (Unique Manuka Factor) is a certification programme run by the UMF Honey Association. Licensed producers test for a combination of markers — methylglyoxal, leptosperin and DHA — and grade on a combined scale.
Leptosperin is the useful addition: it is found in mānuka nectar and is difficult to fake, so it functions as an authenticity marker rather than a concentration one. UMF therefore bundles “how much MGO” with “is this really mānuka” into a single number, backed by licensing and auditing.
Converting between them
Approximate equivalents, which is the best anyone can offer since the systems measure differently:
- UMF 5+ ≈ MGO 83+
- UMF 10+ ≈ MGO 263+
- UMF 15+ ≈ MGO 514+
- UMF 18+ ≈ MGO 700+
- UMF 20+ ≈ MGO 829+
Treat these as a guide, not an exact conversion. A UMF-licensed jar and an MGO-graded jar at nominally equivalent grades are not identical products.
We are not a UMF licensee, so you will not find a UMF grade on a Genesis Honey Co jar. We grade on MGO and publish the laboratory certificate for each batch instead.
KFactor — a different question entirely
KFactor is a brand-specific system focused on pollen content, purity and processing rather than methylglyoxal. A KFactor number tells you something about how monofloral and unprocessed the honey is; it does not tell you the MGO level and does not convert to either scale above.
NPA — the older measure
NPA (Non-Peroxide Activity) is the original laboratory measurement, expressed as a percentage-equivalent. It predates the identification of methylglyoxal and is less common now, though you will still see it. NPA numbers track closely with UMF.
”Active” and “bioactive” — not systems at all
An unnumbered claim like “Active Mānuka”, “Bioactive” or “Premium Mānuka” is not a grading system. There is nothing to compare and nothing to verify. Treat it as no information.
The one that underpins all of them
Separate from grading, New Zealand’s Ministry for Primary Industries sets a scientific definition for mānuka honey: four chemical markers plus a DNA test for mānuka pollen, classifying honey as monofloral or multifloral. All honey exported from New Zealand as mānuka must pass it.
This matters more than which grading badge is on the front. A high number on honey that has not been through MPI testing is a number without a foundation.
What to look for
A specific number rather than an adjective. A named laboratory. Packing in New Zealand. And — the strongest signal of all — batch-level traceability that lets you look up the actual test result for the jar in your hand.
Ours are tested by Hill Laboratories and graded MGO 700+ on that batch’s own result.