Paper is a fine start, but it burns. This guide explains how metal backups work. It is part of Crypto secrets, and it builds on how to back up a seed phrase.
- Slide tiles into a frame
- No tools needed
- Parts can shift if badly crushed
- Punch letters into steel
- Needs a hammer and stamps
- One solid piece
- Letters sealed in a tube
- Compact
- Check for a good seal
Do you need metal?
Start with paper vs metal. If a house fire or flood is a serious concern, or you want a backup that lasts for decades, metal makes sense.
What survives
House fires commonly reach about 1,100°C. Stainless steel and titanium survive that, while aluminum and brass may not. What metal backups survive has the details, including results from public stress tests.
Choose a design
- Stamped or punched plates are the sturdiest.
- Letter tiles need no tools, but parts can shift.
- Capsules are compact.
Compare them in tiles vs stamped plates vs capsules, and see our criteria-led comparison.
Save space with four letters
Every BIP39 word can be identified by its first four letters. See why you only need four letters.
Make your own
A plate and a letter punch set are enough. Follow our DIY guide to stamping steel.