What Size Dehumidifier Do I Need for My Gun Safe?

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What size of dehumidifier do I need for my gun safe? Well, almost every gun owner has faced this nightmare. The humidity inside your gun-safe might turn disastrous to your gun if the size of your dehumidifier is not appropriate. That is why I prepared this guide to help you find the correct size for your dehumidifier.

What Size of Dehumidifier Do I Need for My Gun Safe?

The size of the dehumidifier that you need for your gun safe will depend on the type of dehumidifier that you pick. There are two types of gun safe dehumidifiers: electric dehumidifiers and desiccant dehumidifiers.

The distinctive features for these two are on their effectiveness, prices, and methods of installation. Both have strengths and weaknesses too.

Figuring out what size dehumidifier can fit in this gun safe

For example, an electric dehumidifier that is 12 inches long should cover 100 cubic feet. A dehumidifier that is 24 inches in length should cover 300 cubic feet of a safe. You estimate your measurement around these figures to get a clear picture of what size of electric dehumidifier you need to use.

When you opt for the desiccant dehumidifier, you will need to get the capacity rather than the size. Some of these absorption dehumidifiers like the new and improved Eva-dry E-333 can cover up to around 333 cubic feet.

Determine where the gun safe will be placed, and that will help dictate what type of dehumidifier you need. For example, the garage is a lot different than in your home, in terms of humidity.

How Do I Determine the Size of Electric Dehumidifiers for My Safe?

The size of the electric dehumidifier to be installed will depend on the size of your gun safe. Bigger gun safes require more powerful electric dehumidifiers. You need to get the exact size of your safe for you to find a fitting dehumidifier for it.

You will need to do some calculations to get the correct measurement of your safe: if you are not able to get it from the user manual. For example, if your safe is 7 feet in length, 6 feet in width and 4 feet in height, the total size will be 7*6*4 = 168.

What Are the Benefits of Electric Dehumidifiers?

Electric dehumidifiers usually last longer and are more effective than desiccant dehumidifiers.

If you need enough power for this dehumidifier to function effectively, you have two options:

  • You can purchase a smaller battery pack. In the long run, this could be expensive because the batteries will need regular replacements
  • You can drill a hole on your safe wall to connect it to an external power source

How Do I Determine the Size of Desiccant Dehumidifiers for My Safe?

Desiccant dehumidifiers, also known as adsorption dehumidifiers, are containers filled with hydrophilic materials like silica gel. They are ideal options for safe owners who opt not to use electricity or those who do not want to drill holes in their safe walls.

The gel inside the dehumidifier can absorb moisture or vapor for three to four weeks before you need to recharge them. When using desiccant dehumidifiers, you need to match capacity with the size of the gun safe.

Bigger safes require more capacity of the dehumidifier. These gun safe dehumidifiers vary in capacity and durability. Larger ones cover about 333 cubic feet.

Medium sized dehumidifier for a gun safe

What Are the Advantages of Desiccant Dehumidifiers?

  • Cost-effective: Desiccant dehumidifiers are, in most cases, cheaper than electric dehumidifiers.
  • Easy to Install: The installation process is less complicated as you do not need to drill a hole on the wall of your safe.

What Are The Disadvantages Of Desiccant Dehumidifiers?

  • Not durable: Desiccant dehumidifiers are not durable and may not be a good option for people looking for long-term solutions.
  • They do not absorb all the moisture: This fault is a big concern since there are still chances of your gun getting exposed to some level of humidity.

I recommend that you use the desiccant dehumidifiers if the humidity of your gun safe is low and you are only looking to maintain it. On the other hand, if your safe’s humidity is high, I recommend that you invest both your time and money in purchasing an appropriate size of an electric dehumidifier.

Is a Dehumidifier Necessary in a Gun Safe?

Yes, you need a dehumidifying unit in your safe. While gun safes can resist high temperatures and force, they cannot keep your gun from dampness unless you use a dehumidifier.

Humidity in the environment can sneak into your safe and slowly cause rust, corrosion, and even mildew on both the metallic and wooden components of your gun.

Installing a dehumidifier will give your gun enough protection from the long-term threats of moisture. Failing to monitor the humidity inside your safe could damage the integrity of your gun or ammo.

You need to pick the appropriate size of the dehumidifier that fits your safe. This is because an inappropriate size could cause excess humidity inside the safe that can condense to form water droplets. This vapor or droplets can corrode or cause rust on your gun. The effects of gun corrosion include rust, pitting, inaccuracy, jamming, and misfiring. 


Before making the final purchase decision, you need to consider whether the dehumidifier is a perfect fit according to the size of your gun safe: whether your pick is the electric or the desiccant. When you do this, the functionality and durability of your gun will never be a problem.

James Forrester is a lifelong gun and firearms owner, and an even bigger advocate for gun safety. He created KeepGunsSafe.com with the purpose of sharing helpful tips and educating others on how to keep guns and weapons safe and secure.