What A5, A4 and BMS Scores Mean in Wagyu

You've probably seen labels like A5 Wagyu, A4 Wagyu, or BMS 12 and wondered what they actually mean. Does A5 automatically mean the best steak? And what is a BMS score, anyway?

Understanding the Wagyu grading system can help you make smarter buying decisions and better appreciate what makes authentic Wagyu so highly prized. Here's a simple guide to decoding the numbers and grades behind some of the world's most sought-after beef.

What Is the Wagyu Grading System?

The Japanese Wagyu grading system evaluates beef based on two separate factors:

1. Yield Grade (A, B, or C)

2. Quality Grade (1–5)

Together, these create the final grade you see on a Wagyu product.

For example:

• A5 Wagyu

• A4 Wagyu

• B5 Wagyu

The letter and number each represent different aspects of the beef.

What Does the Letter Grade Mean?

The letter refers to yield, which measures how much usable meat can be obtained from the cattle.

Grade A

Highest yield percentage.

Grade B

Average yield percentage.

Grade C

Below-average yield percentage.

It's important to understand that the letter does not directly indicate flavor or tenderness. An A-grade simply means a higher percentage of usable meat from the carcass.

What Does the Number Grade Mean?

The number measures overall meat quality on a scale from 1 to 5.

The Japanese Meat Grading Association evaluates:

• Marbling

• Meat color

• Firmness and texture

• Fat color and quality

Grade 5

Highest quality.

Grade 4

Excellent quality.

Grade 3

Good quality.

Grade 2–1

Lower quality standards.

This is why A5 Wagyu is considered the highest official grade available: it combines the highest yield grade with the highest quality score.

What Is a BMS Score?

BMS stands for Beef Marbling Score.

Marbling refers to the fine intramuscular fat distributed throughout the meat. It's one of the biggest factors influencing tenderness, flavor, and the signature melt-in-your-mouth experience associated with premium Wagyu.

The BMS scale ranges from:

• BMS 1 = Very little marbling

• BMS 12 = Extremely abundant marbling

The higher the BMS score, the more marbling the beef contains.

How Does BMS Relate to A5 Wagyu?

Many people assume all A5 Wagyu is identical, but that's not actually true.

A5 is a broad category that can include multiple BMS scores.

Typical examples:

Grade	Common BMS Range
A3	BMS 3–4
A4	BMS 5–7
A5	BMS 8–12

This means one A5 steak may have noticeably more marbling than another A5 steak.

An A5 BMS 8 ribeye and an A5 BMS 12 ribeye both qualify as A5 Wagyu, but the eating experience can be quite different.

Is Higher BMS Always Better?

Not necessarily.

While many Wagyu enthusiasts seek the highest marbling possible, personal preference plays a major role.

Higher BMS (10–12)

• Richer flavor

• More buttery texture

• Extremely luxurious mouthfeel

• Smaller portions often preferred

Moderate BMS (6–9)

• Excellent balance of beef flavor and marbling

• Easier to enjoy in larger portions

• Often preferred by first-time Wagyu buyers

Many chefs consider BMS 8–10 the sweet spot because it delivers the signature Wagyu experience while maintaining a stronger beef-forward flavor.

A5 Wagyu vs A4 Wagyu

A common question is whether A5 Wagyu is always better than A4 Wagyu.

The answer depends on what you're looking for.

A5 Wagyu

• Highest official quality grade

• More marbling on average

• Richer eating experience

• Premium pricing

A4 Wagyu

• Slightly less marbling

• More traditional beef flavor

• Often easier to enjoy in larger portions

• Excellent value

Some steak lovers actually prefer certain A4 cuts because they provide a balance between Wagyu richness and classic steak flavor.

How to Choose the Right Wagyu Grade

For first-time buyers:

• A4 Wagyu or A5 BMS 8–9 are excellent starting points.

For special occasions:

• A5 BMS 10–12 delivers the most luxurious experience.

For larger gatherings:

• A4 Wagyu often provides exceptional quality while being more approachable for guests who may be new to Wagyu.

The best Wagyu isn't necessarily the highest grade—it's the one that matches your personal taste and dining experience.

Conclusion

The Wagyu grading system may seem complicated at first, but understanding the basics makes shopping for premium beef much easier. The letter grade measures yield, the number grade measures overall quality, and the BMS score specifically evaluates marbling.

While A5 Wagyu represents the highest official grade, factors like cut selection, BMS score, and personal preference all contribute to the final experience. Whether you're choosing an A4 New York Strip or an A5 Ribeye, understanding these grades helps you appreciate what makes authentic Japanese Wagyu so special.