Metal detector target ID chart: what the numbers mean

Swing over a target and a number appears. It’s tempting to treat that number as a name: 86 means a coin, 12 means a nail.

It doesn’t. The number is the detector’s best guess about how well the target conducts and whether it’s iron. The makers say so in plain words. Nokta’s manual calls target IDs “probable”, in other words “estimated values”.

Three scales, three different answers

Each maker draws its own scale. The figures below come straight from the manuals.

So a target reading 20 is non-ferrous on a Simplex or a Vanquish, but iron on an X-Terra Voyager. That’s why a number quoted on a forum is useless unless you know which machine it came from.

We’ve checked the Vanquish 360 manual only. The Vanquish 340 and 460 may differ; check your own manual.

Minelab Vanquish 360

The manual says negative numbers are ferrous and positive numbers non-ferrous, “ranging from fine gold (low ID’s) to large silver (high ID’s)”.

The scale is split into six discrimination segments of 20 IDs each. Each search mode has its own pattern of accepted and rejected segments. The 360 has three target tones, and the tone breaks “vary slightly for each Search Mode”.

Two notes from the manual worth knowing:

• A non-ferrous target next to iron can read negative.
• All Metal mode can check a signal. A mixed iron and non-ferrous response suggests “a large iron object or a crown bottle cap”. A repeatable non-ferrous response suggests no iron.

Minelab X-Terra Voyager

The Voyager manual prints a target guide. It’s for US targets, and Minelab calls it “a guide only”.

Notice the overlaps. Pull tabs share space with coins and jewellery, and bottle caps share space with silver. The number narrows the field; it doesn’t decide it.

The Voyager has three tones: low, mid and high.

Nokta Simplex

The Simplex scale runs from 01 to 99. Its tones depend on the mode and the model. In Park mode on the Simplex Lite:

• Low tone: ferrous, IDs 01–14.
• Medium tone: gold and non-ferrous, IDs 15–41.
• High tone: non-ferrous such as silver, brass and copper, IDs 42–99.

On the Simplex Ultra’s Park mode the medium band runs 15–69 and the high tone starts at 70. The Ultra’s 4-Tone mode adds a medium-high tone for 71–80.

The manual makes two points every beginner should hear. Gold “may fall within the same range of metal wastes such as iron, foil, screw caps, and pull tabs”. And large targets “will ID higher than expected”.

What about UK coins?

None of the three manuals gives a target ID for a single UK coin. Every example is a US coin.

We won’t invent UK numbers either. Nokta’s advice is the right one: test samples of the coins you expect to find.

How to build your own chart:

1. Collect a few modern coins, a ring-pull, a foil wrapper, a nail and a bottle cap.
2. Wave each over the coil in air and note the number.
3. Bury them at a known depth in your garden and swing again. Expect the numbers to shift.
4. Write the readings down by mode. Your chart, for your machine, on your soil.

Why numbers jump

Nokta’s manual lists the reasons: target orientation, depth, metal purity, corrosion, soil mineralisation, and even the direction of your swing. At the edge of range, a machine may give no ID at all.

Old finds are often corroded, thin or bent. A hammered coin, a lead token or a button can give a weak or wandering ID. That’s why, on old sites, it pays to dig every repeatable non-ferrous signal rather than trusting the number.

Choosing a machine? See our beginner’s detector guide.

FAQ

What do target ID numbers mean on a metal detector?

They're the detector's estimate of how conductive and how ferrous a target is. Low or negative numbers usually mean iron. Higher numbers mean better conductors, such as copper and silver. The makers stress that the number is a probability, not a certainty.

Are target ID numbers the same on every detector?

No. The Vanquish 360 runs from −19 to 99, the X-Terra Voyager from 0 to 99, and the Nokta Simplex from 01 to 99. Each draws its iron boundary in a different place. Nokta's manual says different brands and models produce different target ID numbers.

What target ID is a UK coin?

None of the three manuals gives IDs for UK coins. Their examples are US coins. Nokta recommends testing samples of local coins yourself. Bury a few coins of known type at different depths and note what your machine reads.

Why does my target ID jump around?

Nokta's manual lists target orientation, depth, metal purity, corrosion, soil mineralisation and even the direction of the coil swing as causes. Minelab notes that a non-ferrous target next to iron can show a negative ID.

Should I dig low numbers?

Sometimes. Nokta's manual warns that gold can fall in the same range as iron, foil, screw caps and pull tabs, so you'll dig some rubbish if you want gold. On old sites, that's a good reason to dig every repeatable non-ferrous signal.

Sources

Every figure in this guide comes from one of these. We checked each one on 1 November 2026.

1. Minelab, VANQUISH 360 Instruction Manual (4901-0536-EN-1), Target Identification, pp. 11–12. Copy hosted by Detektormarkt. www.detektormarkt.de/media/7f/1c/88/1771085982/4901-0536-EN-1_Inst_Manual_VANQUISH_360_WEB.pdf?ts=1771085982
2. Minelab, X-TERRA VOYAGER User Manual (4901-0512-2), Target Identification, p. 13, and specifications. Copy hosted by Ames Free Library. amesfreelibrary.org/sites/amesfreelibrary.org/files/attachments/lot/X-TERRA%20Voyager%20Instruction%20Manual%20%28EN%29.pdf
3. Nokta Detectors, Simplex (new generation) User Manual, English, Target ID and Search Modes, pp. 9–11. www.noktadetectors.com/wp-content/file-download/simplex-new-generation/simplex-new-generation-user-manual-en.pdf
4. Nokta Detectors, Simplex LITE specifications. www.noktadetectors.com/metal-detector/simplex-lite/