What is a target ID on a metal detector?

A target ID (sometimes called VDI, for Visual Discrimination Indicator) is a number your detector displays to identify the kind of metal it has found. The number is based on the target's electrical conductivity. Iron and small gold read low; silver, copper, and large brass read high. Most modern detectors use a 0–99 scale, though the exact numbers for a given target vary by detector model and soil conditions.

What's the target ID range for silver coins?

On a typical 0–99 scale, US silver dimes and quarters read in the 80–90 range, half dollars and silver dollars in the 90–95 range. Modern clad coins read close to silver because they share a similar size and shape; clad quarters often hit 85–88. The exact number varies a few points by detector model and soil mineralization.

What target ID does gold read on a metal detector?

Gold reads low — typically in the 50–65 range on a 0–99 scale, which is the same band as foil and pull tabs. This is the hard truth of detecting for gold rings: the productive signals look almost identical to the trash signals. Detectorists who hunt for gold dig everything in that range.

Why does my target ID jump around?

Target IDs become unstable when the target is deep, near other metal, irregularly shaped, on edge, or in heavily mineralized soil. Iron with corrosion can produce wildly varying IDs. The general rule: a clean, repeatable ID is far more trustworthy than a high one. A target that reads steady at 72 every sweep is more dig-worthy than one that swings 30–95 even if it occasionally hits silver.

Are target IDs the same on every metal detector?

No. Each manufacturer sets their own scale and tuning. A US silver dime might read 82 on a Garrett ACE 300, 28 on an older White's, and a different number on a Minelab Equinox. The 0–99 scale is the most common, but values between detectors are not directly transferable. Always learn your specific detector's IDs in your specific soil through field experience.

Understanding Metal Detector Target IDs (VDI): A Complete Guide

An overhead view of a pile of mixed coins recovered from many metal-detecting hunts — pennies, dimes, quarters, and foreign coins — Every coin in this pile produced a target ID before it was ever in a hand.

The number on your detector's screen is the single most useful piece of information it gives you — and the one most beginners misread. A clean, repeatable target ID can tell you with high confidence that you're about to dig a silver dime. A jumpy, unstable ID can tell you with equal confidence that you're about to dig a corroded nail. This guide covers what target IDs actually represent, what the typical ranges mean, why the same coin reads differently in different conditions, and the practical rules for trusting (or ignoring) what the screen is telling you. If you're new to detecting, start with the complete beginner's guide first.

What you'll learn

What a target ID actually is
The target ID chart for common finds
Why the same coin reads differently
Stable IDs vs jumpy IDs
Tones, IDs, and how they relate
Why brands disagree on numbers
Practical rules for trusting an ID
FAQ

1. What a target ID actually is

Every metal has a property called electrical conductivity — how easily an electric current passes through it. Silver and copper conduct well. Iron conducts poorly. Gold falls somewhere in between, but its small size in jewelry pushes its reading lower than its raw conductivity would suggest.

A metal detector measures the conductivity of whatever's under the coil and converts it into a number. That number is the target ID. Most modern detectors use a scale from 0 to 99: iron at the bottom, big silver at the top.

Two important nuances:

Conductivity isn't the only thing the detector measures. Size and shape matter a lot. A small gold ring and a piece of foil have different conductivities, but their similar size makes them read close to each other.
The ID is an estimate, not a measurement. The detector is interpreting a complex electromagnetic response and compressing it into one number. There's always some uncertainty, especially at depth or near other metal.

2. The target ID chart for common finds

Here's a practical chart of where common targets typically read on a 0–99 scale. These are approximate — exact numbers vary by detector, soil, and target condition — but they're a useful mental model for any beginner.

0–30: Iron and ferrous trash

Nails, rebar, rusted bolts, foil-wrapped wire, and most rotting bottle caps. On VLF detectors this range is usually low-tone or "iron grunt." Most experienced detectorists discriminate this out for park hunting. In old sites, however, dig some iron — silver and copper targets next to a nail can grunt as iron because of "masking."

30–50: Foil and pull tabs

The frustration zone. Aluminum foil from gum wrappers, beer-can tabs, and similar light aluminum trash. Reads as a clean mid-tone but produces nothing of value 99 times out of 100. Most park detectorists skip this zone except in known-old areas where it might be a worn coin.

50–65: Nickel and small gold

US 5-cent nickels read here, almost always rock-steady at 52–56. Most gold rings — including wedding bands — also read in this band. This is the band you dig if you're hunting for gold; you'll dig 50 pull tabs for every ring, but the rings come from here.

65–78: Zinc cents and mid-conductivity coins

Modern US pennies (post-1982 zinc-core) read in the low 70s. Older copper pennies read higher (around 78–82) because copper conducts better than zinc. Some thin or worn dimes and dimes in heavy soil also land here.

78–92: Silver and copper

The good zone. Silver dimes (around 80–82), silver quarters (85–88), copper pennies (78–82), and most clad quarters. A clean, steady ID in this range with a sharp high tone is one of the most reliable signals in the hobby. Once you've got the coin in hand, our old-coin identification guide covers how to tell silver from clad and read mintmarks; for series-level catalog data, our sister site LuckyCoin lists every US coin with mintage figures and grade-by-grade values.

92–99: Big silver and large brass

Half dollars (around 90–92), silver dollars (94–96), and large brass objects like belt buckles, buttons, and cartridge cases. The top of the scale is where every detectorist hopes their next signal is headed.

3. Why the same coin reads differently

A US silver dime is the same dime no matter where you dig it. So why does it read 82 in one spot and 78 in another? Several variables push the ID up or down:

Depth. Deeper targets produce weaker signals, and weaker signals are more affected by ground conditions. The same coin can drop 5–10 ID points at the edge of your detector's depth range.
Soil mineralization. Heavily mineralized soil (red clay, black sand, areas with iron deposits) suppresses signals and shifts IDs. The detectorist who hunts in iron-rich soil quickly learns that "82 is the new 88" for silver in their dirt. Proper ground balancing mitigates a lot of this.
Target orientation. A coin lying flat reads cleanly; a coin standing on edge produces a much weaker, often jumpier signal because there's less surface for the magnetic field to interact with.
Corrosion and patina. A heavily corroded copper penny reads lower than a clean one because corrosion changes the surface conductivity. A modern coin out of yesterday's pocket reads differently than one buried for 80 years.
Nearby metal. If there's a nail an inch from your target, the detector is reading both objects at once and producing a confused average. This is "masking," and it's why old sites with iron trash hide coin signals so well.
Coil size and frequency. A bigger coil sees deeper but loses some ID precision on small targets. Higher operating frequencies (12–20 kHz) read small gold and lead better; lower frequencies (5–8 kHz) read large silver better. Multi-frequency detectors split the difference.

4. Stable IDs vs jumpy IDs

The single most useful skill in reading target IDs isn't memorizing numbers — it's noticing whether the number is stable. A clean target produces a clean ID:

Stable, repeatable ID — the same number every time you sweep, regardless of direction. This is what good targets look like.
Jumpy ID over a small range — bouncing 78 / 82 / 80 / 78 every sweep. Often a coin at depth or in mineralized soil. Worth digging, especially if the tone is consistent.
Wildly jumpy ID — 30 / 88 / 12 / 75. Almost always trash, often iron-with-corrosion or two targets close together. A "TID jumping all over the place" target is one of the most reliable trash indicators in the hobby.
Direction-dependent ID — clean number when sweeping north–south, garbage when sweeping east–west. Often a long thin target like a nail (rebar reads as silver one direction and iron the other) or a target on edge. Trust the worse of the two readings.

Practical rule: repeatability beats magnitude. A target that reads steady at 72 every sweep is more dig-worthy than one that occasionally hits 88 but bounces wildly otherwise.

A pair of weathered hands cupping a small pile of silver and copper coins, photographed on a dark background — The payoff of a stable mid-80s ID — a handful of coins worth identifying.

5. Tones, IDs, and how they relate

Most modern detectors map target IDs to audio tones so you can read targets without staring at the screen. The mapping varies, but typically:

Low tone — iron and ferrous trash (0–30).
Mid tone — foil, tabs, nickels, gold (30–65).
High tone — coins, silver, copper (65–99).

Some detectors offer more granular tone schemes (4-tone, 5-tone, full tone-by-conductivity). Multi-tone setups let you hunt with your ears almost entirely — a clean high-low-low pattern is almost always silver next to iron, for example. For a beginner, two- or three-tone is easier; advanced hunters often run full multi-tone in trashy sites.

The strongest skill is learning to trust the combination of a stable tone and a stable ID. Either one alone can lie. Together, they almost never do.

6. Why brands disagree on numbers

One of the most confusing things for new detectorists is that target IDs aren't standardized. A silver dime that reads 82 on a Garrett ACE 300 might read:

Around 28 on an older White's detector (which used a -95 to 95 scale)
Around 28 on a Minelab Equinox (which uses a 0–40 scale internally)
Around 86 on a Nokta Legend

The numbers are not directly transferable between machines. Each manufacturer chose a scale and tuning that made sense to them. What is transferable is the relative position on the scale: silver always reads near the top, iron always reads near the bottom, gold is always in the lower-middle. Once you've learned one detector well, you can pick up another and re-calibrate quickly by remembering which targets fall where.

For this reason, the only target IDs that really matter are the ones you've calibrated yourself, in your own soil, with your own detector. Test by burying a known coin or using one in your hand at known heights — you'll learn far more in 30 minutes of testing than in any number of YouTube videos.

Log target IDs with your finds

After 50 logged finds, patterns emerge: "in my soil, silver dimes read 82–84 at 5 inches." That kind of personal calibration is the single biggest skill jump in the hobby, and it only happens if you write things down. LuckyFind lets you tag every find with a category, target ID, depth, and location so you can spot the pattern over time.

7. Practical rules for trusting an ID

Sweep from at least two directions. A target that reads cleanly only in one direction is suspect. A target that reads cleanly both ways is real.
Trust the lower of two readings. If a target alternates between 78 and 88, assume it's the 78. Iron and trash often produce occasional spikes into the high range; coins almost never produce occasional spikes into the iron range.
Repeatability over magnitude. A steady 65 is more reliable than a jumpy 92.
The depth tax. Targets at the edge of your detector's depth read 5–10 points lower than they would near the surface. Don't dismiss a "low" silver-range signal in deep ground.
Beware the bottle cap. Steel bottle caps can read in the silver range with surprising consistency. The tell is usually a hint of iron grunt mixed in, or a slightly broken signal compared to a real coin. When in doubt at a high-yield site, dig it anyway — bottle caps are the cost of doing business.
Calibrate to your own soil. The only ID numbers that really matter are the ones you've validated yourself. After your first 100 hours, your detector's screen will tell you more than any chart can.

8. Frequently Asked Questions

What is a target ID on a metal detector?: A target ID (sometimes called VDI, for Visual Discrimination Indicator) is a number your detector displays to identify the kind of metal it has found. The number is based on the target's electrical conductivity. Iron and small gold read low; silver, copper, and large brass read high. Most modern detectors use a 0–99 scale, though the exact numbers for a given target vary by detector model and soil conditions.

What's the target ID range for silver coins?: On a typical 0–99 scale, US silver dimes and quarters read in the 80–90 range, half dollars and silver dollars in the 90–95 range. Modern clad coins read close to silver because they share a similar size and shape; clad quarters often hit 85–88. The exact number varies a few points by detector model and soil mineralization.

What target ID does gold read on a metal detector?: Gold reads low — typically in the 50–65 range on a 0–99 scale, which is the same band as foil and pull tabs. This is the hard truth of detecting for gold rings: the productive signals look almost identical to the trash signals. Detectorists who hunt for gold dig everything in that range.

Why does my target ID jump around?: Target IDs become unstable when the target is deep, near other metal, irregularly shaped, on edge, or in heavily mineralized soil. Iron with corrosion can produce wildly varying IDs. The general rule: a clean, repeatable ID is far more trustworthy than a high one. A target that reads steady at 72 every sweep is more dig-worthy than one that swings 30–95 even if it occasionally hits silver.

Are target IDs the same on every metal detector?: No. Each manufacturer sets their own scale and tuning. A US silver dime might read 82 on a Garrett ACE 300, 28 on an older White's, and a different number on a Minelab Equinox. The 0–99 scale is the most common, but values between detectors are not directly transferable. Always learn your specific detector's IDs in your specific soil through field experience.