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Be sure you know everything about runtime

If you decided to acquire a LED flashlight, runtime is a rather significant parameter to consider. If you wonder “What is a runtime?” – here’s the answer. Runtime is defined as the amount of time elapsed from initial switching of the flashlight until the brightness decreases to 10% of the lumen rating in continuous operation. To put it simply, runtime specifies how long a flashlight can function on the same set of batteries. 

Flashlight’s users appreciate longer runtime for a variety of reasons. For example, enthusiastic fishermen get flashlights on the basis of runtime since they don’t want to change the batteries on one of their lasting fishing expeditions. Long runtime is extremely important to backpackers as well – it’s unlikely that somebody wants to think about battery replacement in total darkness. On the whole, runtime determines a flashlight’s performance – high-quality and meticulously designed models will be able to run longer.


Standard for measuring runtime

Before 2009 there weren’t any general rates, which permitted to assess the characteristics of flashlights. For this reason it was rather difficult for users to compare various models in appropriate way. The problem became especially acute when LED flashlights entered the market. 

In comparison with a conventional incandescent light, a LED flashlight could illuminate for a longer distance and time, and use fewer batteries. But there was still no universal system to inform users about these differences. In response to that need, a team of incandescent and LED flashlight producers coordinated with one another to create the standards that would be officially accepted by the National Electrical Manufacturers Association and the American National Standards Institute.  

Widely known as the ANSI FL1 standards, these guidelines are absolutely free-will. There isn’t any necessity for flashlight producers to display the ANSI testing logos. But due to the fact that consumers frequently want to buy devices that are easy to compare, many producers have decided to display the ANSI symbols on their packing. Producers test their devices in accordance with the ANSI FL1 standards, using special procedures.

In whole, the ANSI FL1 standards characterize brightness, beam distance, peak beam intensity, runtime, water- and impact-resistance. Each parameter has its own unique emblem. The ANSI FL1 logo for runtime represents a clock; under which you can see the number of minutes or hours a flashlight can operate on a single set of batteries. The length of runtime is defined as stretching from full power to 10% of a flashlight’s original brightness.

What does runtime depend on?

There are many various factors that can influence a flashlight’s runtime. Let’s clarify how some of them affect it. 

  • Brightness level.

Flashlights with multiple levels of brightness will stop working faster if you use the brightest mode. Runtime is generally measured on the brightest possible mode, which signifies that you may increase a flashlight’s runtime by choosing a lower brightness setting. Remember, the lowest setting will undoubtedly deplete a battery at a much lower rate. That’s why try to use the appropriate setting for the environment to save your batteries.


  • Ambient temperature.

The performance of batteries depends on the temperatures. Different sources of power work differently in cold, heat and humidity. Keep in mind this fact if you are going to apply your flashlight in extreme conditions.

  • Battery type.

Runtime depends to a large extent on the used power supply. Many flashlights are compatible with several types of batteries. But it is widely known that some batteries are more effective in comparison with others. Replacement of battery type, which is used to power your flashlight, can influence the runtime in a certain way.

The more batteries the flashlight has, the longer runtime it will be able to maintain. Batteries of large size always provide more power for prolonged performance. So, when you select a LED flashlight, note how many and what type of batteries each model needs.


It remains to say that you shouldn’t confuse runtime with LED life. LED life shows how long the LED bulbs will be able to operate. For example, the bulbs in a LED flashlight can work nearly 50.000 hours. Nevertheless, that doesn’t in any way imply that they will work 50.000 hours on one set of batteries.

If you are in the wood or in a critical situation, the last thing you want to happen with you is a flickering or dim flashlight. In this case you get stuck in the dark with no means of illumination at all or any signal for help.

Therefore, if you want to avoid such unpleasant situations it’s very essential that you take into consideration runtime when choosing a flashlight.

Armytek Flashlights with the Longest Runtimes

Our mission is to offer the most innovative, best quality products with outstanding technologies that will keep you a step ahead. We use doubled electric circuits in some Armytek flashlights. It means that even when the main circuit is damaged, the system continues to work on reserve circuit emitting during 130 days enough light to enable the user to survive in an emergency case. Stay visible and stay safe with Firefly Technology!

Certain Armytek Pro models have a Firefly mode with output of 0.2 lumens, working for 100 days with ONE 18650 Li-Ion battery.