"Is A5 better than M9? Is USDA Prime the same as A4?" We get this question on WhatsApp most weeks, usually right before a special dinner. The honest answer is the one most shops skip: these aren't one ladder with different rungs. They're four separate grading systems, built by four countries, measuring slightly different things.

So you can't simply line them up and say "this number beats that number." What you can do, once someone explains each system plainly, is match a grade to your budget and your occasion, and stop overpaying for marbling you won't enjoy (or underbuying for the steak night you've been planning).

That decoding is exactly what a curator is for. At iBuddies we carry across origins: Japanese A4/A5, Australian wagyu from marble M2+ up to M9, USDA Prime and Choice, and Korean Hanwoo, so we have no reason to talk up one system over another. Here's how each one actually works.

🇯🇵 Japan: the A5 system (and the myth in it)

Graded by the Japanese Meat Grading Association (JMGA). The famous code, like "A5", is actually two scores stuck together.

The letter (A / B / C) is the yield grade, how much usable meat the carcass gives. A is above-average yield, B average, C below. Here's the part nearly everyone gets wrong: the letter is about cutting yield, not eating quality. A "B" doesn't mean the beef tastes worse than an "A"; it just means a different yield. So the eating quality lives in the number, not the letter.

The number (1–5) is the quality grade, judged on four things: marbling, the colour and brightness of the meat, its firmness and texture, and the colour and lustre of the fat. The catch: the lowest of those four sets the overall grade. So a 5 has to be excellent on all four counts, not just well-marbled.

Within that, marbling has its own finer ruler: the BMS (Beef Marbling Standard), running 1–12. An A5 usually sits around BMS 8–12, but "A5" alone won't tell you where. That's why a precise label like "A5 BMS 10" tells you far more than "A5" on its own.

Left to right: rising marbling, and with it the grade. More fat woven through the meat means richer, more buttery, more tender, and a higher score on every system.

🇦🇺 Australia: marble score M0–M9+ (and MSA)

A lot of the chilled wagyu sold in Hong Kong is Australian, including ours. Australia uses the AUS-MEAT marble score.

The AUS-MEAT Marble Score (MB / MS) runs 0–9, measuring intramuscular fat. Wagyu programs push beyond it, to 9+, and informally up to 10, 11, 12, to track alongside the Japanese BMS range. Separately, Australia also runs MSA (Meat Standards Australia), an eating-quality prediction system that scores tenderness, pH, colour, fat and marbling per cut and cooking method, not a single marble number.

What "M3 to M9" actually feels like on the plate. Higher number = more intramuscular fat = richer, more buttery, more tender, but also more filling per bite:

• M3–M5, balanced and beefy, the everyday-premium sweet spot. Generous steak portions, weeknight-into-special.
• M6–M9, rich, melt-in-the-mouth, indulgent. Best in smaller portions; a little goes a long way.

As a rough orientation only, one widely-cited comparison places USDA Prime Angus at about BMS 3–4, American Wagyu around BMS 6–7, and Japanese A5 around BMS 10–12, useful for picturing where things sit, not for label-to-label maths.

🇺🇸 USA: USDA Prime, Choice, Select

The American system has three top tiers: Prime (the most marbling, roughly the top 2–3% of US beef) > Choice (moderate) > Select (lean). Prime is genuinely excellent everyday-premium beef.

But here's the scale difference made concrete: USDA Prime tops out at roughly BMS 3–4, below where Japanese and high-score Australian wagyu even begin. That's why American Wagyu producers often add a BMS score (around 6–9) on top of the USDA grade: the USDA ladder simply doesn't have rungs high enough to describe wagyu-level marbling. Prime isn't "worse"; it's a different target.

🇰🇷 Korea: Hanwoo 1++ / 1+ / 1

Korea grades its prized Hanwoo beef on its own quality scale, 1++ (highest) > 1+ > 1 > 2 > 3, judged largely on marbling, with 1++ at the top. It's a celebrated premium beef in its own right.

We deliberately won't hand you a "Hanwoo 1++ = A-something" conversion, because there isn't a reliable one. Read Hanwoo on its own terms: a top-tier 1++ or 1+ is Korea's finest, full stop.

Then there's the cut, which matters as much as the grade

Grade tells you how rich the beef is. The cut decides its character and what it's best at.

So, how to choose, by what you're cooking

Forget chasing the biggest number. Start from the meal.

Where iBuddies comes in

We'd rather teach you to choose than just sell you a number: that's the whole point of a curator.

Because we carry across origins and grades, we can sit you in front of the honest options and let you pick the one that fits your table and budget, not push whatever has the highest sticker.

Beyond the website, we run an off-menu chilled (not frozen) wagyu line, sold by the kilogram and ordered directly via WhatsApp. It includes Australian Wagyu Ribeye and Striploin (marble M4–5 or M6–7), Australian Wagyu Short Rib (M2+ or M5–6), Australian Grass-fed Tenderloin, and Korean Hanwoo Striploin (grade 1+ or 1++). It's restocked just a couple of times a month, so it lives off the storefront. Message us for what's in.

And once you've chosen, we finish the job: free custom cutting, with ribeye, striploin and tenderloin cut to the thickness you want, short rib in hotpot slices, all vacuum-packed to hold its quality. Choose well; we'll cut it to suit.

References & Resources

Grading facts in this guide are drawn from the sources below. Cross-system equivalences are presented as approximate only — the systems are run by different bodies and are not officially interchangeable. Last reviewed: 2026-06-04.

• BAR-Ranch / BAR Steaks — Wagyu grading explained (Japanese JMGA yield A–C + quality 1–5, BMS 1–12; AUS-MEAT marble 0–9+; USDA Prime/Choice/Select; indicative BMS comparison): barsteaks.com/wagyu-grading
• Ikigai Fruits — corroborating note on the Japanese Meat Grading Association system: ikigaifruits.com
• AUS-MEAT / Meat Standards Australia (MSA) — Australian marble score and eating-quality grading framework.
• Korean Hanwoo beef quality grades (1++ / 1+ / 1 / 2 / 3) — Korea's national grading system.