Beef · Grading
Japanese Wagyu
A5, BMS 12, and what the letters and numbers actually certify.
Beef from four Japanese cattle breeds, graded A1–A5 for yield and quality and scored 1–12 on the BMS marbling scale. A5 is the top grade. It is intensely marbled, rich enough that a serving is three to four ounces, not twelve.
In one line
The most marbled beef in the world, sold by a grading system that actually means something.
Buy it if
You want the richest beef there is and you are ready to cook it in small portions, hot and fast, with nothing on it but salt.
"Wagyu" just means "Japanese cow" (wa = Japanese, gyu = cattle). It covers four breeds: Japanese Black (Kuroge, about 90% of production and the source of nearly all the beef exported), Japanese Brown, Japanese Shorthorn and Japanese Polled. The genetics predispose these animals to deposit fat inside the muscle rather than around it, which is why a cross-section looks like marble instead of a steak with a fat cap.
Every carcass is graded by the Japan Meat Grading Association on two separate axes, and the familiar "A5" is both of them stuck together. The letter is yield grade — how much saleable meat came off the carcass — A, B or C. The number is quality grade, 1 to 5, and it is the lowest of four sub-scores: marbling, meat color and brightness, firmness and texture, and fat color and quality. One weak sub-score caps the whole grade, so an A5 carcass had to clear all four.
Underneath the quality grade sits the BMS (Beef Marbling Standard), a 1–12 scale measured on the ribeye at the sixth rib. BMS 8 through 12 all grade out as quality 5, so "A5" spans a real range — an A5 at BMS 8 and an A5 at BMS 12 are both A5 and are not the same steak. Sellers who have BMS 11–12 tend to say so.
Regional brands like Kobe, Matsusaka and Omi are Japanese Black raised under a specific prefecture's programme with their own extra rules. They are marketing designations layered on top of the grading system, not higher grades than A5.
At a glance
| What it is | Beef from four Japanese cattle breeds, 90%+ Japanese Black |
|---|---|
| Grading | Yield A–C, quality 1–5, marbling BMS 1–12 |
| Top grade | A5, which covers BMS 8–12 |
| Fat melting point | Around 77–95°F — it softens at hand temperature |
| Serving size | 3–4 oz per person, not a 12 oz steak |
| Best cooking | Hot cast iron, 30–60 seconds a side, no added fat |
| Seasoning | Salt. Occasionally pepper. Nothing else. |
| Authenticity | Real imports carry a 10-digit individual ID traceable to the animal |
Also called
The scale
How it is graded
| A | Yield grade A — above-standard cutability; more saleable meat came off the carcass than the reference standard. B is standard, C is below. Yield says nothing about how the beef eats. |
|---|---|
| 5 | Quality grade 5 — excellent on all four sub-scores: marbling, meat color and brightness, firmness and texture, and fat color and quality. The final number is the LOWEST of the four, so one weak score caps the grade. |
| 4 | Quality grade 4 — good. Corresponds to BMS 5–7. Noticeably less marbled than A5 and, for many people, easier to eat in a normal-sized portion. |
| 3 | Quality grade 3 — average. BMS 3–4. Roughly where high USDA Prime sits, which is the useful comparison point. |
| BMS 12 | Beef Marbling Standard 12 — the top of the marbling scale. The ribeye cross-section reads more white than red. |
| BMS 8–12 | The full range that grades out as quality 5. Every steak in this band is legitimately A5, which is why BMS is quoted separately by sellers who have the high end. |
| BMS 5–7 | Quality grade 4. |
| BMS 3–4 | Quality grade 3 — comparable to upper USDA Prime. |
| BMS 2 | Quality grade 2. |
| BMS 1 | Quality grade 1 — the bottom of the scale. Effectively never exported. |
Myths
What people get wrong
That "Kobe beef" slider is Kobe beef.
Kobe is a regional brand — Tajima-strain Japanese Black raised in Hyogo Prefecture under that programme's rules. Only a few thousand head qualify each year and a small share of that is exported to the entire United States. A "Kobe beef slider" on a bar menu is a name, not a provenance.
Wagyu cattle are massaged and fed beer.
A durable story with no role in the grading. A handful of farms have done both; the marbling comes from breed genetics and a long finishing period on a high-energy ration, typically 600 days or more against roughly 150 for conventional US beef.
A5 is one consistent thing.
A5 covers BMS 8 through 12. That is a wide band — the difference between a BMS 8 and a BMS 12 steak is visible on the plate. Both are honestly labelled A5.
American Wagyu is Japanese Wagyu raised in America.
American Wagyu is nearly always a cross, most often Wagyu bred to Angus. It is excellent beef and marbles far past USDA Prime, but it is not full-blood Japanese Wagyu and is not graded on the Japanese scale.
A5 is best appreciated as a full-sized steak.
The fat renders at close to body temperature and the richness compounds fast. Three to four ounces per person, seared briefly, sliced across the grain, is the portion that works. A 12 oz A5 ribeye defeats most people halfway through.
Compare
Japanese Wagyu vs American Wagyu
Genetics and grading. Japanese Wagyu is full-blood, graded on Japan's A1–A5 and BMS 1–12 system. American Wagyu is a Wagyu–Angus cross graded on the USDA scale, which tops out below where Japanese marbling begins — so it eats like an unusually rich Prime steak rather than like A5.
| Japanese Wagyu | American Wagyu | |
|---|---|---|
| Genetics | Full-blood Japanese breeds | Wagyu crossed with Angus, commonly 50–75% |
| Grading system | JMGA — yield A–C, quality 1–5, BMS 1–12 | USDA — Select, Choice, Prime |
| Typical marbling | BMS 8–12 at A5 | Above Prime, roughly BMS 6–9 equivalent |
| Finishing period | 600+ days | 300–450 days |
| Portion | 3–4 oz | 6–8 oz |
| Eats like | Rich enough to be a course of its own | A very good steak you can finish |
| Price | Highest tier | Above Prime, well below Japanese |
How Crowd Cow sources it
We import full-blood Japanese Wagyu and grade it on arrival, and we also work with American Wagyu ranches running Wagyu–Angus programmes. Both are labelled for what they are — the Japanese imports carry their grade and, where available, their individual animal ID.
Questions
Common questions
What does A5 actually mean?
Two grades stuck together. The A is yield — how much saleable meat came off the carcass, on an A/B/C scale. The 5 is quality, on a 1–5 scale, and it is the lowest of four sub-scores: marbling, meat color and brightness, firmness and texture, and fat color and quality. A5 means the carcass cleared the top band on all four.
Is A5 always the same?
No. A5 covers BMS 8 through 12 on the marbling scale, and that is a visible range. Sellers holding BMS 11 or 12 will usually say so, because it commands more.
Is Kobe better than A5?
Kobe is not a grade. It is a regional programme in Hyogo Prefecture that raises Tajima-strain Japanese Black under extra rules, and Kobe beef is itself graded on the same A1–A5 scale. An A5 from another prefecture is graded identically.
How much should I serve per person?
Three to four ounces. The fat starts rendering at close to body temperature and the richness builds quickly — A5 works as a course, not as a 12-ounce main.
How do I cook it?
Dry cast iron, screaming hot, no oil — the steak renders more than enough of its own fat. Thirty to sixty seconds a side, rest briefly, slice across the grain into strips, salt at the end. Do not marinate it and do not cook it past medium-rare.
How do I know it is real?
Genuine Japanese imports are traceable: every animal carries a 10-digit individual identification number that resolves to its birth farm, breed and grading. Ask for it. "Wagyu" on a menu with no grade, no prefecture and no ID number is usually a domestic cross at best.
Buy it by weight, not by the steak
Read the weight on each card before you compare prices. These are sold in small pieces on purpose — a Wagyu steak is not a steak-sized portion, so the numbers on two cards are rarely comparing like with like.
