Coin Pinger
Acoustic bullion authentication — free, private, on-device
Open data · CC BY 4.0
The coin resonance dataset
Every reference on this site in one machine-readable table: physics-computed resonance modes, tolerance bands, confidence tiers, and cited official specifications for 68 gold and silver coins. Free to use with attribution to Coin Pinger (coinpinger.com).
Version 2026-07-24 · updated whenever the reference library changes.
What's in it — and where the numbers come from
One row per coin: name, metal, fineness, issuing mint with source link, official weight/diameter/thickness, the c0d2/c0d3/c0d4 resonance modes in Hz, per-mode fractional tolerance bands, and a confidence tier. The resonance values are computed from first-principles free circular-plate physics — the mint's published mass and diameter, materials-science elastic constants, and Leissa's classical eigenvalues with rim and thick-plate corrections — not measured from sample coins. The complete model is documented in the methodology and implemented in the open-source repository (MIT).
License: Creative Commons Attribution 4.0 — use it in your app, research, or spreadsheet, with attribution to "Coin Pinger (coinpinger.com)". Modes above 20 kHz are omitted (phone microphones can't read them reliably), so small coins carry one or two modes.
Browse the same data as guides
Every row has a human-readable page with the physics explained: silver · gold · most popular · fractional sizes — or compute a coin we don't list with the resonance calculator.