Backing up your seed phrase

Your seed phrase backup has to survive two opposite dangers. One is losing it. The other is someone else finding it. Good storage balances the two.

The two dangers

Loss. Fire, flood, a house move, a tidy relative, or simply forgetting where it is.
Exposure. A burglar, a visitor, a cleaner, or anyone who sees a photo of it.

Every choice below trades one against the other. More copies protect against loss and add chances of exposure.

Keep it off every screen

The first rule has no exceptions. Do not store the phrase:

In a photo or screenshot
In a notes app, document or email
In cloud storage
In a password manager

bitcoin.org warns that "any backup that is stored online is highly vulnerable to theft". Malware searches devices for exactly this.

Paper

Paper is fine to start with. Use a pen, write clearly and number the words. Its weaknesses are fire, water and fading.

Simple improvements:

Use good paper and permanent ink.
Seal it in a waterproof bag.
Keep it in a fire-resistant box or safe.

Metal

For savings you plan to hold for years, consider a metal backup. These are steel plates on which you stamp, engrave or punch the words.

The engineer Jameson Lopp has stress-tested 75 of these products for heat, corrosion and crushing. His general finding is useful whatever you buy: "Simpler is better - more pieces means more potential points of failure." In his tests, single solid plates were among the most durable designs and the best value.

Avoid any backup product whose maker creates or could know your phrase.

How many copies, and where?

bitcoin.org's advice is that "single points of failure are bad for security". A practical arrangement:

Two copies in two separate places, so one fire or flood cannot destroy both.
Each place locked and private, such as a home safe and a bank deposit box or a trusted relative's safe.
Not next to the hardware wallet. If a thief finds both, the PIN is no obstacle.

Do not label the backup with words like "bitcoin" or "wallet".

Do not invent your own scheme

People lose coins to clever ideas: splitting the phrase into halves, changing the word order, hiding words in a book. These make recovery harder for you and your family and often weaken security. If you want stronger protection, use the standard tools in Lesson 38.

Maintenance

Test it. A backup is unproven until you have restored from it, as in Lessons 27 and 29.
Check it once a year. Confirm it is still there and still readable.
Stay quiet. The fewer people who know you hold crypto, the fewer will look.
Plan for your family. Lesson 39 covers what happens if you are not around.