Flank comes from the cow’s lower abdominal area, below the loin and behind the plate. It is a lean, fibrous beef cut often sold as flank steak; cook beef steaks to 145°F and rest 3 minutes.
What Part Of The Cow Is Flank From: flank is 1 of the beef primal cuts, taken from the cow’s lower abdominal area, below the loin and behind the plate.
It is a long, flat, lean muscle section from the belly side of the animal. Because that area works hard, flank steak has visible grain, strong beef flavor, and less tenderness than rib or loin cuts.
The Short Answer, With Numbers
Flank steak comes from the cow’s lower abdominal area, directly below the loin and behind the plate. It is one flat, long, lean muscle from the belly side, not from the rib, round, chuck, or brisket.
On a beef carcass, flank is located on each side of the animal. That means 1 cow has 2 flank sections: a left flank and a right flank. Each side can yield 1 main flank steak.
Where It Sits On The Cow
Think of the cow in 3 simple landmarks: ribs in the middle, hind leg at the back, belly underneath. Flank is the lean sheet of muscle under the loin, forward of the rear leg, and behind the lower rib/plate area.
It is an abdominal muscle, so it works more than tenderloin but less like a shank. That is why flank is lean, visibly grained, and best sliced thin across the grain.
A typical flank steak is much wider than it is thick. In U.S. grocery cases, it is commonly sold as 1 whole flat steak, not as several thick individual steaks like ribeye or strip.
| Relevant beef item | Safe minimum internal temperature | Rest time | How it applies to flank |
|---|---|---|---|
| Beef steaks, chops, roasts | 145°F (63°C) | 3 minutes | Use this for whole flank steak cooked as a steak. |
| Ground beef, pork, veal and lamb | 160°F (71°C) | None | Use this only if flank is ground into ground beef. |
| Leftovers, reheated | 165°F (74°C) | None | Use this for reheated cooked flank steak leftovers. |
Worked Examples
If you buy a package labeled “beef flank steak,” treat it as a whole beef steak. Cook it to 145°F, then let it rest 3 minutes before slicing.
If a butcher grinds flank into burger meat, the category changes. It is no longer handled as a whole steak for temperature purposes. Ground beef is 160°F with no rest time.
If last night’s cooked flank is sliced for tacos today, it falls under leftovers when reheated. Reheated leftovers are 165°F with no rest time.
If flank is rolled, tied, or used inside a casserole with meat or poultry, do not rely on the plain-steak number. A meat or poultry casserole is 165°F with no rest time.
Names That Can Confuse The Cut
Flank is not skirt steak. Skirt comes from the plate/diaphragm area and is usually narrower with a looser grain. Both are lean, fast-cooking cuts, but they are different muscles.
Flank is not London broil by anatomy. “London broil” is often a cooking method or retail name. It may be flank, but it can also be another lean beef cut.
Flank is also not brisket. Brisket is from the lower chest. Flank is farther back and higher into the abdominal side, near the rear underside of the carcass.
The practical number to remember: 1 cow gives 2 flank steaks, and a whole flank steak uses the beef-steak figure of 145°F plus a 3-minute rest.
Where Flank Steak Comes From
Flank steak comes from the cow’s lower abdominal area, below the loin and sirloin, behind the plate, and in front of the round. It is cut from the flank primal, not from the rib, chuck, brisket, or short loin.
On a beef side, the flank sits on the underside of the animal. Picture the cow’s belly line: brisket is forward, plate is mid-belly, flank is farther back, just before the hind leg section called the round.
Exact Butcher Location
The flank steak is mainly the rectus abdominis muscle. This long, flat muscle helps support and move the abdomen, so it has visible grain and more chew than tenderloin or ribeye.
A typical flank steak is about 1 to 2 pounds, roughly 12 to 14 inches long, 5 to 8 inches wide, and about 3/4 to 1 inch thick. One cow yields only 2 flank steaks, one from each side.
- 1. Start at the beef side: A butcher works from one half of the carcass. The flank is on the lower rear belly, not the top back. If the cut came from the backstrap area, it is not flank.
- 2. Find the plate: The plate is the belly section closer to the front ribs. Skirt steak comes from this area. Flank is farther back, past the plate, toward the hindquarter.
- 3. Find the round: The round is the rear leg and rump section. Flank sits immediately in front of it. If the cut is from the hind leg itself, it is round steak, not flank steak.
- 4. Identify the muscle: True flank is a single, flat abdominal muscle with long fibers running lengthwise. The grain is easy to see before cooking, which is why slicing direction matters.
- 5. Trim the surface: Flank usually has little internal marbling but may have surface fat or membrane. Butchers trim it close, leaving a lean, wide, oval-to-rectangular steak.
- 6. Separate similar cuts: Skirt is thinner, looser, and from the diaphragm or plate. Hanger is thicker and from near the diaphragm. London broil is a cooking name, not the same location.
Worked Example: Reading a Meat Case Label
If a package says “beef flank steak,” expect one flat steak weighing about 1.5 pounds. For 4 servings, that gives about 6 ounces raw per person before cooking loss and trimming.
If the label says “flank steak strips,” it should still come from the same abdominal muscle. The strips are just cross-cut or length-cut pieces from the flank, often sold for fajitas or stir-fry.
If a label says “London broil flank,” the meat may be flank, but “London broil” alone can also be top round. Check for the word “flank” if you want the specific cow location.
Because flank is a worked abdominal muscle, it is lean and strongly grained. For beef steaks, the USDA safe minimum internal temperature is 145°F with a 3-minute rest.
The key identification rule is simple: flank is the cow’s lower rear belly steak. It is behind the plate, ahead of the round, below the loin, and cut as one broad, lean, grainy muscle.
Flank Location On The Cow
Flank comes from the lower belly of the cow, below the loin and sirloin, and behind the plate. On a side of beef, it sits on the underside of the animal, roughly between the last ribs and the rear leg.
Think of the cow in 3 horizontal bands: back, middle, and underside. Rib, loin, and sirloin are high on the back. Chuck and round are toward the ends. Flank is in the underside band, near the rear half.
Exact Position Relative To Other Cuts
The flank primal is bordered by the plate toward the front, the round toward the rear, and the loin above it. It is not from the ribs, not from the hip, and not from the brisket.
On a hanging side of beef, flank is a thin, flat area below the short loin and sirloin. The flank steak is cut from the abdominal muscles, mainly the long, visible-grained muscle in that region.
| Nearby area | Position compared with flank | Common cuts |
|---|---|---|
| Short loin | Above flank | Strip steak, T-bone, porterhouse |
| Sirloin | Above and slightly rearward | Top sirloin, tri-tip area |
| Plate | Forward of flank | Skirt steak, short ribs |
| Round | Behind flank | Top round, eye round |
| Brisket | Farther forward and lower chest | Brisket flat, brisket point |
Why Flank Looks Different
Flank is an abdominal working muscle. It helps support movement and posture, so it has long muscle fibers and a clear grain running lengthwise across the steak.
A typical flank steak is broad, flat, and tapered. Many retail pieces are about 1 to 2 inches thick at the thick end, with a rectangular or slightly oval shape.
One whole flank steak commonly weighs about 1.5 to 3 pounds. A 2-pound piece cut into 4 equal servings gives 8 ounces raw per serving before trimming and moisture loss.
Flank Versus Skirt And London Broil
Flank and skirt are often confused because both are flat and strongly grained. The location is the key difference: skirt is from the plate, forward of the flank, while flank is farther back on the belly.
London broil is not a cow location. It is a retail or cooking name. A package labeled London broil may be flank, but it may also be top round or another lean cut.
If the label says “flank steak,” it should come from the flank primal. If it only says “London broil,” check the fine print for the actual cut name.
How To Identify It At The Meat Case
Look for a single flat steak with fibers running in one obvious direction. The grain is usually much easier to see than on ribeye, sirloin, or tenderloin.
The piece should be relatively lean, with little internal marbling. Some surface membrane or silver skin may appear, especially near one edge.
For slicing, the location matters because the grain is long and tough. Cut cooked flank across the grain into thin slices, often 1/4 inch thick or less, to shorten the muscle fibers.
For safety, flank steak is a beef steak cut. The USDA safe minimum internal temperature for beef steaks is 145°F, followed by a 3-minute rest.
Why Flank Is Lean
Flank is lean because it comes from the cow’s lower abdominal area, below the loin and behind the plate. That section is built for support and movement, not fat storage.
On a side of beef, the flank is a relatively flat muscle group. The main retail cut, flank steak, is usually about 1 to 2 inches thick and commonly weighs 1.5 to 3 pounds.
The key muscle is the rectus abdominis. It helps stabilize the body and assist movement. Because it works often, it develops long, visible muscle fibers and relatively little internal marbling.
Movement Creates Dense Muscle, Not Marbling
Muscles that do more work tend to be firmer and leaner. Flank sits in a high-use zone, unlike rib or loin areas that do less daily work and usually carry more intramuscular fat.
That is why flank has a pronounced grain. The fibers often run nearly the full length of the steak. A 12-inch flank steak may show grain lines running 10 inches or more end to end.
Marbling is fat inside the muscle. Flank has little of it. Most visible fat is on the outside surface, where it can be trimmed before cooking.
Example: if a 2.25-pound flank steak has a 3-ounce exterior fat patch, trimming removes about 8% of its starting weight. The remaining meat is still mostly dense muscle fiber.
By contrast, a heavily marbled steak keeps much of its fat inside the meat. You cannot trim that away without cutting through the steak itself.
Why Flank Can Still Taste Beefy
Lean does not mean bland. Flank has strong beef flavor because the muscle is well-exercised. The tradeoff is texture: it can seem chewy if sliced with the grain.
For serving, slice across the grain. If the fibers run left to right, cut top to bottom. A 1/4-inch slice across the grain shortens each bite into tender, manageable fibers.
A worked example: a 2-pound flank steak loses about 15% during cooking, leaving roughly 1.7 pounds. At 4 ounces per serving, that yields about 6 to 7 portions.
If sliced with the grain, those same portions chew tougher because each bite may contain long fibers. Cut across the grain, and the same steak eats noticeably softer.
Edge Cases: When Flank Looks Fatty
Some flank steaks have a thick membrane, silver skin, or exterior fat cap. That does not make the cut well-marbled. It means the butcher left more surface trim attached.
A choice-grade flank may show a few fine streaks of fat. A select-grade flank may look almost bare. Both are still lean compared with cuts from the rib or short loin.
Skirt steak is often confused with flank. Skirt comes from the plate area and is usually thinner, looser-grained, and fattier. Flank is broader, flatter, and more uniform.
Flap meat is another lookalike. It comes from the bottom sirloin, not the flank. It can have more loose texture and uneven thickness than a true flank steak.
For doneness safety, beef steaks, chops, and roasts should reach 145°F and rest 3 minutes. Use that figure for flank steak too, since it is a beef steak.
The lean structure is the main reason flank benefits from marinades, fast cooking, and thin slicing. Those steps do not add marbling, but they help manage the dense muscle fibers.
How Butchers Cut Flank
Flank comes from the cow’s lower abdominal wall, below the loin and behind the plate. A butcher removes it as a single, flat muscle from each side of the carcass, so one beef animal yields 2 flank steaks.
The muscle is long, lean, and visibly grained. In a typical retail case, one trimmed flank steak weighs about 1.5 to 2.5 pounds and measures roughly 12 to 18 inches long, 5 to 8 inches wide, and about ¾ to 1 inch thick.
Where the Knife Line Runs
On the carcass, the flank is taken from the area under the sirloin and short loin, near the belly. The butcher separates it along natural seams instead of sawing through bone, because flank is a boneless muscle.
The upper edge is freed from the loin area. The lower edge is trimmed away from the abdominal membrane and connective tissue. The front end sits closer to the plate; the rear end runs toward the round.
A whole flank has a tapered shape. One end is wider and thicker, while the other narrows. This is why slices from the thick end may look broad, while slices from the tapered end can look short and narrow.
Trimming: What Gets Removed
Butchers usually remove the tough surface membrane, ragged edges, excess fat, and any silver skin. A heavy trim can reduce the piece by several ounces, especially if the outer membrane is thick.
Example: a 2.3-pound untrimmed flank may become a 1.9-pound retail steak after removing 0.4 pound of membrane, fat, and uneven edges. That is about a 17% trim loss.
Some stores sell flank “peeled,” meaning the membrane has been removed. Others leave a thin layer attached. If the surface looks shiny, tough, or papery, it likely needs more trimming before cooking.
Cut Direction and Portioning
Butchers generally leave flank whole because it cooks more evenly as one flat steak. For kebabs or stir-fry, they may cut it into strips, but the grain direction matters more than the strip length.
The grain usually runs lengthwise from end to end. For tender eating, cooked flank is sliced across the grain, not with it. A 16-inch steak may be cut into 3 shorter sections first, then sliced crosswise.
Worked example: if a flank is 15 inches long and the grain runs the full length, slicing with the grain gives long, chewy fibers. Turning the knife 90 degrees creates shorter fibers, often ¼ inch wide per slice.
For fajitas, a butcher may cut a 2-pound flank into 4 sections of about 8 ounces each. Each section should still be sliced across the grain after cooking, or into raw strips cut against the visible muscle fibers.
Edge Cases at the Meat Counter
Flank is not the same as skirt steak. Skirt comes from the plate and diaphragm area and is usually thinner, looser grained, and longer. Flank is wider, flatter, and more uniform.
It is also not the same as flap meat, which comes from the sirloin area. Flap is often more irregular and chunkier. If the label says “sirloin flap,” it is not flank.
If a package contains two narrow strips instead of one broad sheet, ask whether it is flank, skirt, or flap. True flank is normally one clean, oval-to-rectangular muscle from the abdominal flank section.
Cuts Often Confused With Flank
Flank comes from the cow’s abdominal area, below the loin and behind the plate. It is a single, flat, lean muscle with long, visible grain. Several thin beef cuts look similar in the package but come from different places.
Flank vs. Skirt Steak
Skirt steak is the cut most often mistaken for flank. Skirt comes from the plate section, closer to the diaphragm, while flank comes from the lower belly area behind it.
A typical flank steak is wider and more rectangular. It often weighs about 1.5 to 2.5 pounds and may be 10 to 14 inches long. Skirt is usually longer, narrower, and thinner.
Texture is the giveaway. Flank has straight, lengthwise fibers. Skirt has looser, more open fibers and more surface ridges. If the grain looks like thick ropes, it is more likely skirt.
Worked example: if a steak is 13 inches long, 6 inches wide, and fairly even in thickness, treat it as flank. If it is 20 inches long, 3 inches wide, and ribbon-like, it is probably skirt.
Flank vs. Flap Meat
Flap meat, also sold as sirloin flap or bavette, comes from the bottom sirloin. It can look like flank because it is flat and grainy, but it is usually looser and more irregular.
Flank is usually one clean slab. Flap meat may have uneven edges, folds, and a shaggy surface. In a tray pack, flap often looks like 2 or more connected lobes rather than 1 neat rectangle.
For slicing, both need attention to grain. On flank, the grain usually runs clearly from end to end. On flap, the grain may shift direction across the piece, so divide it before slicing if needed.
Flank vs. London Broil
London broil is not a cow location. It is a cooking or marketing name. Stores may label flank as London broil, but top round is also commonly sold under that name.
This causes confusion because top round is thicker and comes from the rear leg, not the abdominal flank. A top round London broil may be 1.5 to 2 inches thick, while flank is often thinner and flatter.
Edge case: if the label says “London broil” and the meat is oval, thick, and very uniform, assume it is not flank unless the package also says “flank steak.”
Flank vs. Hanger Steak
Hanger steak comes from near the diaphragm, not the flank. It is usually smaller, thicker in the center, and divided by a tough membrane that may be trimmed out by the butcher.
A whole hanger often has 2 lobes. Flank does not. If the cut looks like a pair of long muscles joined down the middle, it is more likely hanger than flank.
| Cut | Where It Comes From | Main Clue |
|---|---|---|
| Flank | Abdominal area | Wide, flat slab with straight grain |
| Skirt | Plate, diaphragm area | Long, narrow, rope-like grain |
| Flap | Bottom sirloin | Loose, uneven, shaggy surface |
| Top round London broil | Rear leg | Thicker, oval, very uniform |
For beef steaks, chops, and roasts, the safe minimum internal temperature is 145°F with a 3-minute rest. That applies whether the package says flank, skirt, flap, hanger, or London broil.
Frequently Asked Questions
What part of the cow does flank steak come from?
Flank steak comes from the cow’s lower abdominal area, behind the plate and below the loin. It is a flat, long muscle from the belly side, not the ribs or round. Because this muscle works a lot, flank is lean, beefy, and noticeably grained.
Is flank steak the same as skirt steak?
No. Flank steak comes from the lower abdominal flank area, while skirt steak comes from the plate section near the diaphragm. Both are thin, flavorful cuts with visible grain, but skirt is usually fattier and looser-textured.
Flank is typically wider, thicker, and leaner.
Is flank steak a tough cut of beef?
Flank steak can be tough if overcooked or sliced incorrectly because it comes from a hard-working abdominal muscle. For tenderness, cook it quickly, let it rest if cooked to 145°F, and slice thinly across the grain at about a 45-degree angle.
What is flank steak best used for?
Flank steak is best for fajitas, stir-fries, steak salads, tacos, London broil-style dishes, and sandwiches. Its broad, flat shape takes marinades well and cooks fast. One flank steak commonly serves about 4 people, depending on portion size and side dishes.
Where is flank located compared with brisket and round?
Flank is on the underside of the cow, in the lower belly area. Brisket is farther forward in the chest, while round is at the rear leg. So flank sits between those zones: behind the plate, under the loin, and ahead of the hindquarter.
