Cryptoetch can be purchased at Claims to be:

  • Waterproof
  • Fireproof
  • Corrosion Resistant


This is really interesting because it’s the first of its kind. Cryptoetch makes it dead simple to safely create a steel backup via electrochemical etching. Basically, you remove the protective varnish for the words you want etched and then use salt water and electricity to burn away a few layers of steel.

The initialization of the Cryptoetch is a bit more involved than most, but at least it’s not physically taxing or straining on your ears. My one gripe about the product is that there are no numbers or lines to guide you when writing on the varnish. If the manufacturer could pre-set those, it would be an improvement in my opinion.

The etching process was straightforward, but requires patience. Personally I’m not so sure about the use of felt strips for distributing the salt solution; it makes it harder to tell if any etching is occurring. I ended up just covering the whole device in salt water and directly placing the metal pen onto it so that I could observe the bubbling. Recommended time results in 1 hour of etching to complete both sides.

I’ll also note that by the time I had a single side etched, it completely drained my 9 volt battery. So you’ll want to have several available in order to get the job done.

Heat Stress Test

No visible damage, however the covers are stuck and don’t rotate, making it impossible to read the seed. Cyphersafe told me ahead of time that if I encountered problems with the cover, it would be fairly easy to pry it off. I’m going to wait until after the other tests are completed to do that, as I have no reason to believe that the seed phrase has been compromised. When shaking the device I couldn’t hear any tiles rattling around, so I don’t think they came loose.

Corrosion Stress Test

Oddly enough, it seems that if anything the words might be MORE legible now.

Crush Stress Test

Given the thickness of this steel block, it’s extremely difficult to deform. No data loss.