What do the NIJ Body Armor Levels Mean?

The NIJ protection levels represent the type of ammunition / ballistics that the body armor is designed to resist when facing threats.

Note that the National Institute of Justice doesn’t test the product’s individual materials, but rather what the armor is capable of protecting against.

A bullet cannot make a hole or pierce the vest for armor to meet NIJ standards. The vest also needs to protect against blunt trauma, such as that from a swung pipe or baton.

While the basic protection levels go up to five, you may come across a Level I armor, which no longer meets NIJ standards as it has low caliber resistance., but it exists in the used market.

Checking the NIJ body armor levels is essential as it indicates the type of threat a specific armor protects you from. Luckily, the National Institute of Justices has created a chart that summarizes the standards they use to certify body armor performance against the different levels of threats.

NIJ Level IIA is the level ascribed to any soft body armor consisting of layers with high-strength woven fibers. Body armor that falls under this rating generally weighs less than ten pounds, making it maneuverable and agile.

The common materials used to make Level IIA body armor includes Goldflex, Twaron, or polyethylene fibers like Dyneema and Spectra. Bulletproof vests rated Level IIA have a maximum thickness of 4mm.

This type of body armor is designed to stop a .9mm FMJ round at 1165 ft/s. It’s also been tested with a .40 S&W Full Metal Jacket at 1065ft/s. It’s common in soft body armor vests used by civilians and law enforcement officers looking for protection against low-impact ballistic fire.

NIJ Level IIA is flexible, lightest, comfortable, and simplest to conceal.

Unfortunately, despite Level IIA body armor being flexible and lightweight, it won’t stop a high-velocity round and leave bruising when shot.

• .gmm FMJ (Full Metal Jacket) at 1165 feet per second (ft./s)
• .40 S7W(Smith & wesson) FMJ at 1065 ft/s

After Level IIA is the NIJ Level II, it’s also a soft body armor but slightly heavier and thicker than is Level IIA body armor.

Measuring 5mm thick, this body armor is designed to protect the wearer from .9mm FMJ traveling at 1245ft/s and a .357 Magnum Jacketed Soft Point at -1.430ft/s. Level II also protects against most standard handgun rounds.

Similar to Level IIA, Level II is also simple to conceal, comfortable, and light. However, the major difference is that it provides better protection against blunt force trauma. That includes any trauma caused by the kinetic energy of the round hitting the vest or plate, adding increased protection against tissue damage from blunt forces.

The primary users of Level II armor are the police and private security.

Bulletproof vests under Level II have layers of bulletproof or other aramids.

Level II vests can protect you against a high range of ammunition compared to Level IIA. Furthermore, they provide more blunt force protection compared to IIA.

Although Level II soft body armor can withstand multiple spaced hits, it’s advisable to verify an armor’s threat-specific stopping power and multi-hit capability with any brand, model, or armor level.

On the downside, Level II can be challenging to take off and put on quickly if worn concealed.

• all handgun rounds, up to and including .357 magnum jacketed soft point (JSP)

Level IIIA armor is versatile while offering a significant level of protection.

NIJ Level IIIA is capable of stopping .357 Sig FMJ flat nose bullets that travel at a speed of -1470ft/s and .44 Magnum Semi Jacketed Hollow Point rounds at 1430ft/s. The armor also protects against shotgun slugs and most handgun rounds.

Similar to Level II and Level IIA, Level IIIA mainly consists of soft armor. It’s the most popular protection level you’ll see when looking for soft body armor.

Vests under this rating deliver the perfect balance between comfort and protection. As a result, IIIA is considered the highest level of soft body armor.

However, it’s common to find ballistic shields and rigid armor plates with an NIJ rating of IIIIA.

Level IIIA is heavier than Level IIA and II, but you can still conceal it. You’ll find it in bulletproof backpacks and bulletproof vests.

• .9 mm rounds traveling at speeds of up to 1400 ft/s
• .44 magnum rounds

Level III armor protects against rifle rounds and represents the first level of rated hard body armor. In contrast to soft body armor, Level III has rigid inserts, also known commonly as rifle plates or ballistic plates.

NIJ Level III plates are engineered to stop six spaced hits of 7.62 x 51mm NATO Full Metal Jacket traveling at a speed of 2,750 ft/s. That is similar to the .308 Winchester hunting round, a round common in hunting rifles designed to be a ‘one shot one kill’ platform.

But that’s not all. Level III rated body armor is also tested to multiple hits of six rounds on a single plate. Unlike the previous levels, Level III is rigid, making it less agile, and somewhat challenging to effectively conceal.

However, the tradeoff made with heavier armor is that it offers a greater degree of protection than soft armor, and is thus more advisable in higher risk situations where the chance of high velocity and/or rifle round impacts are a possibility.

You may also come across rigid armor rifle plates labeled as Level III+. Again, this rating is not on NIJ’s list of standardized ratings, but the ‘+’ is indicated for armor is designed to protect from additional specific threats, such as that from an M193 or M855.

Level III body armor plates are available at varying price points depending on the rifle plate’s material and weight. You can find expensive plates made from ceramic or polyethylene that weighs close to three pounds, making them lightweight and easier to wear for longer periods of time or when traveling any distance on foot is required. Cheaper plates are heavier and are typically made from steel, and often weigh upwards of up to 10lbs.

• .9 mm rounds traveling at speeds of up to 1400 ft/s
• .44 magnum rounds

Level IV is the highest rated hard armor plate under NIJ 101.06 standards. Any armor under this rating provides ultimate protection against gunfire and a wide range of ballistic projectiles.

These armor plates are designed to take a single hit from an armor-piercing rifle. The plates are capable of defeating 7.62MM armor-piercing bullets traveling at a speed of 2880 feet per second. Impressive.

One thing to note is that a Level IV body armor is not always better than Level III armor, and which is most appropriate for your needs depends on your assessed level of threat and other factors.

Level IV plates are only tested to stop a single shot, unlike a Level III hard armor plate that’s been tested for six shots.

Of note is that Level IV armor lacks flexibility, and its weight can make it uncomfortable to wear for long hours. However, military officers and other security forces are issued with Level IV body armor. It requires some form of training to put on and is designed for a combat situation.

• .gmm FMJ (Full Metal Jacket) at 1165 feet per second (ft./s)
• .40 S7W(Smith & wesson) FMJ at 1065 ft/s