Lumens are a unit of measurement that describes a light’s total light output.

For tactical lights, having more output is always a good thing. If you’re trying to fill a dark room and identify potential threats, you’ll need a high-output light that can illuminate the room from corner to corner. Lumens are a good basic measurement to compare different lights by overall output—but Lumens don’t tell the full story. For example, lanterns may produce a lot of light overall, but in a tactical setting, only a small portion of that light will be useful.

To fully understand a light’s practical output, you’ll need to understand its beam pattern and Candela rating.

Candela is a unit of measurement that describes a light’s peak intensity.

Like Lumens, Candelas are an important factor when evaluating a light’s output and performance. If a light isn’t bright enough, it won’t be able to illuminate a target obstructed by rain, fog, gun smoke, or a photonic barrier. High-intensity lights can also blind a target, making it harder for them to attack you, which is why police often deploy high-intensity lights when subduing threatening suspects at night.

When shopping for weapon lights, you will want to consider both Lumens and Candelas together. Lights with high Candela ratings may have a smaller beam of light, but more of that light will be focused at the center, making it easier to see things at a distance. If a light has low Candela and high Lumen ratings, it’ll have a wide beam, which can be more beneficial in close quarters.

Lumens and Candela can help you understand the two fundamental characteristics of a tactical light’s beam pattern: throw and spill.

Throw is the light’s ability to reach out to far distances, like when you’re trying to see what’s across a field or in a tree line. Most of your throw will come from the intensity of a light’s center ‘hotspot’.

Spill is the peripheral light outside the hotspot. Spill light won’t have much range, but it can be lifesaving in close-quarters, where threats often in the corners of a room.

To understand how Lumens and Candela can inform your understanding of how a light will perform, let’s give an example.

If two weapons lights have a 500-Lumen output, but one light has a higher candela, its concentrated beam will be more intense and make up a larger percentage of the light’s overall lumen output.

A 500-Lumen light with a higher Candela rating will send more of its power out into the distance, allowing you to see further. The 500-Lumen light with a lower Candela measurement will cast more of its lumen output into the spill light, making the center hotspot less powerful but offering more ambient light at your periphery.

In this scenario, the weapon light provides intermittent bursts of light as you move through your home, illuminating areas of negative space to ensure that it is clear of any threats.

In this setting, spill is more important than throw, so you should prefer lights with high Lumen ratings and low-to-medium Candela ratings.

A wide beam can light up larger areas of a room with greater efficiency, allowing you to scan the room instantaneously. If your light lacks the spill to fill a room, you’ll be giving an opportunity to any threat that hides outside its beam.

The other advantage of a wide beam is that its blinding effect will affect a larger area, making it easy to disorient a potential attacker. If you are clearing a room with a narrow beam and started scanning on the wrong side of the room, you won’t disorient the intruder and you’ve just exposed yourself with the light’s source.

We briefly touched on the benefits of having a weapon light attached to your rifle for nighttime hunting and varmint control, especially with colored lens filters.

But what if your primary home defense weapon is an AR-15, SBR, or AR pistol, and you need to secure your home from the outside? If you live in a more rural setting and wish to investigate the area surrounding your home after the sun goes down, you’re going to have much different light requirements than someone who is indoors, inspecting areas of their home in the dark.

Outdoors, you will need light to be projected in a concentrated beam of light that can reach out to further distances. The tradeoff is that less of the immediate area around the light will be illuminated.

However, if you are outdoors and have eyesight acclimated to the low light environment, using a more concentrated light beam at further distances will often allow your eyes to remain able to perceive the immediate environment without illumination.

In this setting, you’ll want a light with a high Candela rating. You should also try to get the most lumens possible, but Candela will be a more important indicator of throw.

If you’ve taken one thing away from these past few questions, hopefully the most significant thing is the fact that a weapon mounted light should be considered a vital piece of your home defense and overall preparedness solution.

But what’s the best AR light or pistol light for you? We’ve laid out some of the most trusted and highest quality weapon mounted lights for both pistols and rifles. Keep your particular needs and performance requirements and use this knowledge to make an informed decision.

Pistol Mounted Lights

Rifle Mounted Lights

If you're looking for some additional flexibility, a popular solution for a weapon light configuration is to mount a high-quality handheld flashlight onto a rifle with a special mount.

The benefit to this is that you get a EDC (Every Day Carry) flashlight to carry with you all the time.