Security alert · 30 Jul 2026: a seed-generation flaw in Coldcard devices was disclosed. What to do →

Metal seed backups: tiles, punched or engraved?

TL;DR

Tiles are fastest, punched plates can’t come loose, engraved or stamped plates are cheapest and permanent. Each fails differently, which is why I keep two different kinds in every box.

Letter tilesPunched plateEngraved / stamped
ExamplesCryptosteel, BillfodlBlockplateBlank steel plate
Time for 24 wordsAbout 30 minutesAbout an hourOne to two hours
Tools neededNoneCentre punch, hammerStamps and hammer, or rotary tool
Can letters move?YesNoNo
Easy to read backYesTakes careYes, if done neatly
CostHighestMiddleLowest

Why failure modes matter

A backup that fails in an obvious way, such as melted or unreadable, sends you to your other backups. A backup that fails quietly, with the right words in the wrong order, can cost you hours of confusion at the worst moment. Tiles can fail quietly. Punched and engraved plates don’t.

My setup

A tile backup for speed and readability, plus an engraved plate with the same words as a check. Both in the same box, because they’re the same key. Tools and plates:

Whatever you pick

  • Stainless steel or titanium only, never aluminium or brass.
  • First four letters per word is enough.
  • Check the plate on the device, not just against paper (step 5).