The detection range on your typical metal detector depends on the factors that go into the design of the device. I can tell you now that the size of the rotator coils, the strength of the electromagnetic waves, and the size of the metal detector itself all factor into how deep it can detect.
Whether you have decided to use your metal detector to look for hidden treasure on the beach, or if you want to make sure that you haven’t left any metal inside your backyard, you need to understand the depth that your device brings. Everyone knows how a metal detector works, but I’m going to ask you, how deep does your metal detector go?
Well, most metal detectors have a range that can detect different types of metals reliably. This all depends on the type of metal detector that you end up using, and the object that you are looking for.
There are hundreds of metal detectors on the market. All of them have a wide range of depths. Below is a look at different factors that fit into the depth equation.
How Deep in the Ground Can a Metal Detector Detect?
There are typically three sizes of metal detectors: small, medium, and large.
Small metal detector
Can detect objects about 10-20 centimeters in the ground
Medium metal detectors
Can detect objects 30-45 centimeters under the ground
Large metal detectors
Some of them can go 20 meters deep.
Note that the above depths are averages. These can depend on the type of detector you are using, the type of minerals in the ground, and the frequencies that the metal detector can use. Here are some of the things you need to look at for your metal detector when calculating depth. They should help you to make informed choices going forward.
What You Are Looking For
Most metal detectors are designed to pick up metal objects through the ground. The object you are looking for has a massive influence on the type of unit that you buy. Consider the size of whatever it is you may be hoping to find.
Your detector is more likely to pick up larger objects deeper in the ground, because of the larger surface area. Additionally, the shape of the target also comes into play. Wider objects with are also likely to be much easier to detect. Finally, if your target is laying down horizontally, you stand a better chance of picking it up.
To give you an easy visual for reference:
| Position/Size | Can It Be Detected Easily? |
| Is It Wide? | Yes! |
| Is it Large? | Yes! |
| Is it Horizontal? | Yes! |
You might not be able to see the item that you are looking for, but you should have some type of idea of what you want. If you are looking for a large metal box inside of the ground, you might find it very easily since it’s so large Looking for a small nail, (yes, I know the example is extreme) even inside of shallow soil or sand, is going to be harder be harder with the same metal detector.
What Affects the Depth of Your Metal Detector?
Three things tend to affect how deep your metal detector can go: The frequency of the metal detector, the software that the detector is running, and its shape.
I’m going to break down all three for you.
| Frequency | Affects the Electromagnetic Waves |
| Software | Affects the Ground Balance and Discrimination |
| Search Coils | Affects the Electromagnetic Field |
Frequency
All metal detectors have a frequency. The frequency signals how many electromagnetic waves the machine can transmit into the ground per second. These waves are what allow you to figure out what is underneath the ground. There are two types of waves.
The first is a single frequency. It can continuously emit the same level of electromagnetic waves into the ground. You aren’t going to be able to change the frequency, so what you buy is what you get.
The type of frequency that you are using can help you find certain metals or targets under the ground. For example, a low frequency is under 8 kHz, which is suited for locating large and very conductive targets, such as silver or copper.
Bigger frequencies such as those over 40 kHz are sensitive to smaller metals. If you know the material composition of what you are looking for, then you can use the frequency that is going to be sensitive to that type of metal.
If you don’t have that knowledge, then you might need to look at a multi-frequency metal detector. This type of unit emits several frequencies at different kHz levels at the same time. This casts a wide net and allows you to get more detection for your buck.
Software
Metal detectors also have software features that affect how deep the metal detector can detect. Ground balance is a feature that can counterbalance the ground mineralization (or the false signals caused by the natural levels of iron or salt in the soil). The ground balancing software achieves this by muting the signal from the minerals in the ground, and only detects the targets you set.
Discrimination is also something that your metal detector can do. You can program the software to ignore the properties of a certain metal. For example, if you don’t want your detector beeping at the site of a few iron nails in the ground, you can reprogram it to ignore them. The detector can discriminate against the highly magnetic properties of the iron and only pings when it gets to other metals.
Search Coils
Finally, you have the search coils (the two round objects at the end of your metal detector) that can help to detect the disturbances in the electromagnetic field. The coils allow you to find different objects easier. The size of the search coil increases the size of the electromagnetic field and the depth that the metal detector can go to.
Small search coils are concentrated and can easily pinpoint objects in crowded areas with a lot of minerals. Larger coils can go deeper into the ground and can cover a much broader search area.
The most common coil shape you are going to find is concentric coils. This consists of a larger outer coil that generates the electromagnetic field and a small inner coil that receives the signals from objects in the ground.
How Deep Can a Metal Detector Detect Gold?
Of course, one of the most common uses for a metal detector is to detect gold.
Gold has several properties that you need to take into account before you grab your metal detector to start looking for it:
- It is conductive
- It is reflective with regard to heat and light
- It is heavy and dense
Typically, whenever you start looking for gold, you are looking for small nuggets. I should also tell you that larger pieces are extremely rare, and most of them have already been found. The high conductivity of gold allows for your metal detector to target it with the electromagnetic pulse and easily find it amid the sea of less conductive metals.
A metal detector can detect gold at just a generous depth, but you are much more likely to find smaller pieces of gold at the surface of the ground. Still, even a very small nugget of gold can bring you some good money!
How Deep Can a Harbor Freight Metal Detector Detect?
One of the best brands of metal detector is the brand Harbor Freight. Harbor Freight has been giving the world tools since 1977. It’s wanted to make sure that you get the highest quality tools at some of the lowest prices imaginable. It offers all sorts of tools, but the pride and joy of the collection has to be the 9 Function Metal Detector. It’s a fairly basic detector, but it more than makes up for its simple design with the depths it can get to.
The 9 Function Detector can detect objects about 6 – 8 inches deep under the ground. This does depend on the soil and the object that you happen to be looking for, but you can easily customize the sensitivity knob. Just twist it and you can crank up the sensitivity.
Another knob controls the discrimination of the detector. You can set it to beep at detecting all metals to find everything. Another twist lets you filter out certain metals.
It can filter out these listed metals:
- Iron
- Aluminum
- Silver
If you still want to get a notification for whenever you are over a filtered-out metal, a tone knob allows the metal detector to play a special tone whenever you pass over one of those metals.
For example, you can customize your 9 Function Harbor Freight metal detector to distinguish any iron inside of your yard from common objects. After all, no one likes it when their metal detector starts beeping for the iron in a nail!
The 9 Function Harbor Freight metal detector is a great basic option to find items that are buried inside your yard, local beach, and other places. If you want a more specialized option for serious and deep metal hunting, then look down below.
Which Metal Detector Has the Best Depth?
While the depth of most metal detectors depends on various factors, there’s still a type that outshines the rest in most categories. They are designed to be used for serious hunters.
These metal detectors are high tech and expensive, and they are not for beginners. The Makro DeepHunter 3D Pro is a very expensive purchase that takes everything great about metal detectors and puts it all into the same machine.
First, the Makro comes with a 3D graphic display. It not only shows what the metal detector is picking up, but it shows the location of cavities in the earth. These cavities are typically where mineral deposits are more likely to be found. The display also separately displays each segment.
Allowing you to tailor your scanning to include only certain things, such as:
- Precious metals
- Gold
- Cavities in the earth.
Even without the 3D graphic display, it still comes with selectable frequencies and an increased detection depth. You can use the various knobs on the side of the device to increase or decrease the discrimination for different types of metals. Additionally, different types of sounds play whenever you go over certain types of metals.
You don’t need to worry about highly mineralized soil and other problems getting in the way of the deep scans. You should easily be able to find what you want to find, thanks to the advanced filtering options. Just be careful because even if you can stomach the price tag, you might balk at the weight: The Makro DeepHunter weighs in at 14 pounds, so even if you find nothing on the field, you can still be pumping iron having to carry the machine around!
The weight can change based on the coils that you choose to use, and whether you choose to bring the 3D imaging system. Even without it, you are still carrying around 8 pounds of weight. That’s certainly not for the faint of heart!
| The Weight | 14 pounds |
| The Coils | Comes with a T44 and T100 Coil |
| The Projector | A detachable Imaging system |
Increasing Metal Detector Depth
Of course, you might not want to spend the big bucks on a new metal detector. Thankfully there are a few ways to increase the metal detector depth on your own machine. First, make sure that you are cranking up the sensitivity on the detector.
The more sensitive that your metal detector is, the more it can pick up. Increasing the depth can:
- Improve the likelihood of picking up items
- Improve the functional depth of the detector
However, this can be a double-edged sword. If you are in an area with very mineralized soil or lots of iron-based trash and debris, then the metal detectors can go haywire if the sensitivity is turned up too much.
You should also turn on the ground balance function and keep the function tuned regularly. With the ground balance turned on, the detector is not going to be triggered by the mineralization of the ground. This means that more of its power can be sent underground to increase how deep it can go.
Keep It Low to the Ground and Your Signal Clear
If you keep your metal detector very low to the ground, you can make sure that your detector is getting the additional depth. Ideally, it should barely be off the ground. If vegetation or plant life makes getting close to the ground impossible, you need to either remove the obstacle or get a heavier metal detector.
The usage of a heavier metal detector should allow you to push the vegetation out of the way, without damaging the detector or the plants.
You need to keep the signal clear whenever it comes to using your metal detector. The unit is creating an electrical field around you whenever it is in operation, and that delicate field can be interfered with.
You might get interference from things such as power lines and electrical items in your immediate area. You could even have something on your person messing with the signal.
Bits of metal in your shoes, items in your pockets, and other things you have could be warping the signal. Pocket clutter such as your cell phone and keys are often the most likely suspects if your signal is bouncing around.
For the best results, make sure that you are metal free while using your metal detector. Also, store your phone and other metal pocket clutter somewhere else while you are working.
To deal with outside interference such as telephone wires or other electrical signals, you can try to turn down the sensitivity of the metal detector. It is admittedly a last resort and something that you need to figure out through trial and error, but it can work for you.
Heck, you might even find something that other people missed once you get a good signal.
What Goes into a Good Metal Detector?
You may worry about what types of Metal detectors can go deep enough for your needs. However, if you are a beginner, I’d say you need to focus on thinking about what makes a good metal detector.
First, you should look for an all-purpose metal detector from the best metal detectors list. Unless you instinctively know ‘I am going to look for gold and only gold,’ an all-purpose metal detector is something that can pay for itself. It can find just about anything. Thankfully, you can also find these metal detectors at various prices.
You also want to get a few accessories and make sure that your metal detector has some of these abilities:
- Very good pinpointing abilities
- Discrimination features
- Sensitivity tuning
- The ability to compensate for ground mineralization
Where Are You Going to Look for and How Often?
Where are you going to be hunting for items? Are you going to be inside your backyard, at fairgrounds, at parks, or around mountains? Where you are looking for items has a large impact on the type of metal detector that you should buy. It also affects what you should look for.
For example, most gold rings and jewelry are found around lake shores and along the beach. To find those precious artifacts you need to go and get a metal detector that is strong enough to be around water. In most cases at the beach, the metal detector is going to be partially or fully submerged in the water, so make sure that it is waterproof.
As stated before, if you are looking at a place where the grass and vegetation is very heavy, you need to get a very heavy metal detector. This can allow you to sweep the heavier vegetation away and get the detector close to the ground, which should allow it to penetrate much deeper.
You also need to look at how often you are metal detecting. While it can be interesting to grab a metal detector to find a lost ring or locket that you or someone in the family dropped, you might end up falling in love with the hobby. If you plan to keep exploring with your metal detector, then you might want to upgrade it to a model that can withstand repeated use.
The unit is going to get bumped, scraped, jolted, damaged, and dropped over the course of its lifetime. If you want the machine to last, you need to make sure that it is a rugged model and it can withstand a few battle scars.
Do some research before purchasing a metal detector. Don’t just looking at the depth of the machine, but also looking at how durable it is. You want a unit that can stand the test of time with you.
Look at Your Experience
Whenever I first got my metal detector I wanted one that was a quick plug and play. All I wanted was to be able to put my batteries into it, turn it on, and then start looking around for hidden treasures.
I got a metal detector with automatic tuning and pre-set discrimination settings that is on the best metal detector brands list. With it, I was able to zero in on the treasures to avoid junk and the common minerals of the ground. The tuning let me learn about and then control the various conditions I could change, and I learned at my own pace.
As my experience level and knowledge of the metal detector and how it worked grew, I began using more and more of the higher tier features. Then I found more stuff and improved my knowledge through trial and error. Eventually, I bought a new metal detector that does everything I need it to.
You need to do the same. If you are a beginner to the art of hunting with a metal detector, then start with one that comes ready to use out of the box. If you have some knowledge under your belt, you might consider one that has more features you can fiddle around with. For those of you that have serious time and money, you can get one of the higher tier ones that can have a steeper learning curve.
Get Started with Your Metal Detector Today
Using a metal detector is easy once you get the hang of it. Like all skills, however, it can be very hard to master. Your metal detector can detect pretty deep items and hidden treasures. Once you become familiar with using it, who knows what treasures you might find?
