Metal backups come in three main designs. This comparison is part of our metal seed phrase backups guide.
- 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
At a glance
| Design | How it works | Tools needed | Time to set up | Durability |
|---|---|---|---|---|
| Stamped plate | Punch letters into solid steel | Hammer and punches | 1 to 2 hours | Excellent |
| Punched grid | Mark dots on a printed grid | Center punch | About 1 hour | Excellent |
| Letter tiles | Slide tiles into a frame | None | 1 to 3 hours | Good |
| Capsule | Stack letter rings in a tube | None | 1 to 3 hours | Good |
Stamped plates
You punch each letter directly into the metal. There are no moving parts, so the words cannot fall out. Downsides are noise, tools and a learning curve. Mistakes also cannot be fixed. See our DIY guide.
Punched grids
These plates have a printed alphabet grid, and you punch a dot to mark each letter. It needs less skill than stamping, and it is quieter. One device can be compact, and they have done well in public tests. Accuracy matters, because a misplaced dot is a wrong letter.
Letter tiles
You slide small metal tiles into channels. It needs no tools, and it is easy to correct a mistake. In a crushing impact, the frame can bend or spring open. Screws and security seals help. Fill any empty slots with blanks, so that the tiles cannot move.
Capsules
A capsule stacks letters inside a metal tube. It is small and easy to hide, but you may be limited to a few letters per word, and you need to confirm that it holds all 24 words.
How to choose
| If you… | Choose |
|---|---|
| Want the toughest option | Stamped or punched plate |
| Do not have tools or space to hammer | Punched grid or tiles |
| Want to correct mistakes easily | Tiles |
| Want something very small | Capsule |
| Are on a tight budget | DIY plate |
Whichever you choose
- Use four or more letters for each word. See why four is enough.
- Check the backup against your words, and test it.
- Store it just as carefully as paper.
For evidence about durability, see what metal backups survive, and our full comparison.