If you've ever stood in front of a shelf of Manuka honey — or scrolled through an online store — you've probably noticed two different rating systems: UMF™ and MGO. Both appear on quality Manuka honey, but they measure slightly different things and can cause real confusion for buyers.
This guide breaks down exactly what each rating means, how they relate to each other, and which one you should use to guide your purchase.
What Is MGO?
MGO stands for methylglyoxal — the naturally occurring compound responsible for Manuka honey's unique antibacterial properties. The higher the MGO number, the more methylglyoxal is present, and the stronger the antibacterial activity.
MGO is measured in milligrams per kilogram (mg/kg). So an MGO 263+ honey contains at least 263 mg of methylglyoxal per kilogram.
MGO ratings are straightforward: a single compound, a single number. But they don't tell the whole story.
What Is UMF™?
UMF™ stands for Unique Manuka Factor — a grading system developed and trademarked by the UMF Honey Association (UMFHA) in New Zealand. It's a more comprehensive quality standard that tests for three key markers:
- Leptosperin — a compound found only in genuine Manuka nectar, used to verify authenticity
- DHA (dihydroxyacetone) — the precursor to MGO, indicating freshness and future potency
- MGO — the active antibacterial compound
Because UMF™ tests for all three markers, it's considered the gold standard for verifying that a honey is:
- Genuinely from the Manuka flower (Leptospermum scoparium)
- Fresh and properly stored
- Potently antibacterial
Only licensed producers who are independently audited can display the UMF™ trademark on their labels.
How Do UMF and MGO Ratings Compare?
| UMF Rating | MGO Equivalent | Strength |
|---|---|---|
| UMF 5+ | MGO 83+ | Entry level |
| UMF 10+ | MGO 263+ | Moderate |
| UMF 15+ | MGO 514+ | High |
| UMF 20+ | MGO 829+ | Very high |
| UMF 22+ | MGO 1000+ | Premium |
| UMF 25+ | MGO 1202+ | Ultra premium |
| UMF 30+ | MGO 1620+ | Ultra rare / Special Reserve |
Which Rating Should You Trust?
Both ratings are valid, but UMF™ offers stronger consumer protection because:
- It's independently audited by the UMFHA
- It tests for authenticity (leptosperin), not just potency
- It's a licensed trademark — producers must meet strict standards to use it
- It accounts for freshness via DHA testing
MGO-only labelling can be self-reported and doesn't verify that the honey is genuinely from Manuka flowers. Some products from outside New Zealand have used MGO claims without the authenticity checks that UMF™ requires.
Our recommendation: Always look for the UMF™ trademark alongside the MGO number. If a honey only shows MGO with no UMF™ certification, ask why.
Which UMF Strength Is Right for You?
UMF 5+ (MGO 100+) — Mountain Gold UMF 5+
Great for everyday wellness, adding to tea, smoothies, or toast. A gentle introduction to Manuka honey.
UMF 10+ (MGO 263+) — Mountain Gold UMF 10+
A popular all-rounder. Good for immune support, digestive health, and daily use.
UMF 15+ (MGO 514+) — Mountain Gold UMF 15+
Recommended for those seeking stronger therapeutic benefits — wound care, sore throats, gut health.
UMF 20+ (MGO 829+) — Mountain Gold UMF 20+
High-potency honey for targeted health applications. Popular with health-conscious buyers who want maximum benefit.
UMF 22+ (MGO 1000+) — Mountain Gold UMF 22+
Premium strength. Often chosen as a gift or for specific wellness protocols.
UMF 25+ (MGO 1202+) — Mountain Gold UMF 25+
Our most potent honey. Ultra-premium, rare, and reserved for those who want the very best.
UMF 30+ (MGO 1620+) — Mountain Gold UMF 30+ Special Reserve
Our rarest and most extraordinary honey. Special Reserve grade — exceptionally limited, with unmatched potency. For those who seek the absolute pinnacle of New Zealand Manuka honey.
Not sure where to start? Browse our full Manuka Honey collection or try our UMF 5, 10 & 15+ Gift Pack — a great way to explore different strengths.
The Bottom Line
- MGO measures the antibacterial compound methylglyoxal — useful, but incomplete on its own.
- UMF™ is a comprehensive, independently audited standard that verifies authenticity, freshness, and potency.
- When buying Manuka honey, look for both ratings on the label, and always check for the UMF™ trademark.
At Mountain Gold, every jar is UMF™ certified and sourced from our hives in the pristine Mount Bruce region of New Zealand. You can trust what's on the label.
Have questions about which strength is right for you? Contact us — we're happy to help.