What do the numbers on a metal detector mean?

They're the target ID — an estimate of what metal is under the coil, based on conductivity. Low numbers mean iron and foil, middle numbers mean nickels, gold and pull tabs, and high numbers mean copper and silver coins.

What number is gold on a metal detector?

Gold typically reads low to mid — roughly 10–35 on a 0–99 scale — which unfortunately overlaps almost exactly with pull tabs and foil. There is no number that means gold and nothing else.

What number is silver on a metal detector?

Silver reads at the top of the scale, usually 75–95. It's the most conductive thing you're likely to dig, which makes silver coins the easiest targets to identify with confidence.

What number is iron on a metal detector?

Iron reads lowest, generally 0–10, and usually sounds broken or raggedy rather than clean. The exception is heavily rusted iron, which can read deceptively high.

Why do the numbers keep jumping around?

A bouncing ID usually means iron, several objects close together, or a target too deep for a confident reading. A genuine single coin holds a steady number from most sweep directions.

Is there a standard target ID chart for all metal detectors?

No. Every manufacturer scales its IDs differently, so the same coin gives different numbers on different machines. Test known coins on your own detector and write down what it says.

Should I dig low numbers?

Not usually, unless you're relic hunting where iron is the point. Just know that discriminating out the low-to-mid range also removes your chance at gold, which reads right alongside the trash.

Answer · Updated August 18, 2026

What Do the Numbers Mean on a Metal Detector?

Short answer

The numbers on a metal detector are the target ID — the machine's guess at what kind of metal is under the coil, based on how conductive it is. Low numbers mean iron and foil, high numbers mean silver and copper. It's a strong hint, not a promise.

The numbers on a metal detector are the target ID, usually on a scale of 0–99. They tell you how conductive the buried object is: iron and foil read low, coins read middle to high, and silver reads highest of all.

Learning to read them is the difference between digging every signal and digging the ones worth your time. But treat the number as evidence rather than a verdict — depth, angle, and rust all push it around.

01The target ID chart

Every manufacturer scales this slightly differently, so treat the ranges below as the shape of the thing rather than gospel. A Minelab, a Garrett and a Nokta will each give a different number for the same quarter.

Target ID	Usually means	Dig it?
0–10	Iron — nails, bottle caps, rusted junk	No, unless you're hunting relics
10–20	Foil, very small gold, thin chains	Sometimes — gold hides here
20–35	Pull tabs, small gold rings, nickels	Yes if you want gold jewelry
35–55	Screw caps, larger gold, zinc pennies	Usually yes
55–75	Copper pennies, dimes, quarters	Yes
75–95	Silver coins, large copper, half dollars	Always

Approximate ranges on a 0–99 scale. Check your own detector's manual — a nickel reads 12 on some machines and 30 on others.

02Why gold is the awkward one

Here's the fact that costs beginners the most: gold reads in the same range as pull tabs. A thin gold ring and a discarded can tab are close to identical in conductivity, and no detector can reliably separate them.

This is why experienced beach hunters dig pull-tab signals all day long. Everyone who has found a gold ring found it by digging something that read like trash. If you discriminate out that range to save time, you are also discriminating out the gold.

03When the number lies

Depth flattens everything. A deep silver coin loses conductivity apparent to the machine and can read as a mid-range target or bounce erratically. Faint, deep signals deserve digging even when the number looks unremarkable.

Rusted iron reads high. A badly corroded nail can produce a solid, convincing coin number — the halo of rust around it confuses the machine completely. This is the single most common false dig.

Two targets together average out. A nail beside a coin gives you a reading that matches neither. If the number changes as you sweep from different angles, there's more than one thing down there.

Big objects read high regardless. A buried can lid reads like a silver dollar because size raises apparent conductivity just as much as metal type does.

04How to actually use the number

The number is one input. Tone, depth reading, and how the signal behaves from multiple angles matter just as much — and the sequence below is what most experienced detectorists run through without thinking about it.

1Sweep from two directions, ninety degrees apart. A good target holds roughly the same number both ways. Iron usually jumps around.
2Listen to the tone, don't just read the screen. Your ears catch the raggedness of an iron signal faster than your eyes catch a flickering number.
3Check the depth reading. A high number at shallow depth is often a bottle cap; the same number at eight inches is far more likely to be real.
4Pinpoint before digging. If the target spreads out rather than tightening to a point, it's probably large junk.
5When genuinely unsure, dig it. Especially early on — digging trash is how you learn what trash sounds like on your machine.

05Every detector numbers things differently

There is no industry standard. A US nickel might read 12 on one machine and 30 on another, and some detectors use a two-digit ID while others use a segmented scale with no numbers at all.

The practical fix takes twenty minutes: build your own chart. Lay a nickel, a zinc penny, a copper penny, a dime, a quarter, a pull tab, a bottle cap and a nail on the grass, sweep each one, and write down what your detector says. That handwritten list is more useful than any chart online, including this one.

Keep reading

Detectors worth a look

Minelab Equinox 800 review
One detector to cover coins, jewelry, beach, and the occasional gold hunt — without compromising on any of them.
Garrett Ace 400 review
A first detector for parks, fields, and dry ground — someone who wants to be finding coins the same day it arrives.
Nokta Simplex+ review
Beginners and second-machine buyers who want waterproof capability — creeks, lakes, rain, and freshwater swim beaches.

Buying guides

Best Pinpointers for Metal Detecting
The best pinpointer for metal detecting is the Garrett Pro-Pointer AT — waterproof, adjustable, and hard to lose. Probes compared for dirt, water, and gold.
Best Pinpointer Metal Detector for Gold
The best pinpointer for gold is the Falcon MD20 — a very high frequency probe that finds flakes in quartz standard pinpointers miss. Gold probes compared.
Best Metal Detector for Kids
The best metal detector for kids is the Nokta Mini Hoard — light enough for a small child and capable enough to find real coins. Picks by age, from 5 to teenager.