Numbers in your head: memorising a numeric seed

A copy in your head can't be found in a drawer or read at a border. It also can't be inherited, and it fades. Memory still has a place, as long as it is never the only copy.

Memory is the second copy

Never make your memory the only copy of a seed. Memory fails under stress, illness and age, and your family can't recover anything from it. Keep the written copy (disguised, as numbers) and treat the memorised copy as a backup that travels with you.

The one secret that often belongs in your head is the passphrase, with a written copy stored somewhere apart (the 25th word). If you memorise only one thing, make it that.

Words or numbers?

With this site's method you have two forms of the same seed: the twelve or twenty-four words, and the numbers from your cipher. They are not equally easy to hold.

	The words	The cipher numbers
What to remember	12 or 24 words	48 or 96 digits, plus the cipher name
To recover	Type them in	Fetch the cipher, decode, then type them in
Built-in check	The BIP-39 checksum	None until decoded
Picturable	Mostly (pizza, kiss, copper)	Only with a system

BIP-39 chose its words so the first four letters identify each one, and many are concrete nouns. That makes the words the easier thing to memorise. The checksum helps too: BIP-39 tells wallet software to warn when it fails, so a misremembered word usually shows up. (For a 12-word phrase, one wrong word slips past the 4-bit checksum about one time in 16.)

Memorise the numbers when you want your head copy to match your paper copy exactly, or when you'd rather that what you rehearse never sounds like a seed phrase. You then also need the cipher name, and the tables, to get the words back.

The peg system for numbers

Four-digit numbers are hard to hold. Images are easy. The peg system (often called the major system) turns digits into consonant sounds, so you can build a word for any number and picture it. Vowels and the letters w, h and y count for nothing.

Digit	Sound	Digit	Sound
0	s, z	5	l
1	t, d	6	j, sh, ch
2	n	7	k, hard g
3	m	8	f, v
4	r	9	p, b

It goes by sound, not spelling: the b in comb is silent, so comb is k-m, 73.

Make yourself a fixed list of 100 pegs, 00 to 99, one picture each, and learn it once. Every four-digit cipher number is then two pictures. The public example in the 8 January 1784 cipher:

pizza educate fat kiss domain venue kingdom raise split step copper time (this phrase is public: never use it for real funds)

starts 5432 6201 6211 6173. With one common peg list:

Number	Pegs	Pictures
5432	54 + 32	lure, moon
6201	62 + 01	chain, suit
6211	62 + 11	chain, dad
6173	61 + 73	sheet, comb

Then link each pair into one scene: a fishing lure hooked on the moon; a suit wrapped in chain. A strange, loud or moving scene sticks better than a plain one.

The memory palace for order

The order matters as much as the numbers. The memory palace (the method of loci) handles order. Quintilian described it in the first century: choose a large house you know, walk through it room by room, and leave one image in each place. To recall, walk the route again and collect them.

1. Pick a route you know cold: your home, a walk to work, a building you grew up in.
2. Fix 12 or 24 stops along it, in order: front door, coat hook, hall mirror, kitchen sink. Use the same stops every time.
3. Put one number's scene at each stop: the lure-and-moon at the front door, the chained suit on the coat hook.
4. Walk it back. Front door: lure, moon, 54 32, 5432.

The same route works for words. Put a pizza on the front door and something being educated on the coat hook, and skip the peg step entirely.

The method can be trained. In a 2017 study published in Neuron, people with no memory training practised the method of loci for 30 minutes a day over 40 days. Their recall of 72-word lists improved well beyond the control groups', and they kept much of the gain at a check four months later.

Keep it honest

1. Rehearse on a schedule: the next day, a week later, a month later, then every few months.
2. Rehearse by walking the route, not by reading the paper copy.
3. Once a year, check the memory against reality. Offline, on your signer, enter the words (decoded from the numbers if that's what you memorised) and your passphrase, and compare the wallet fingerprint with the one you wrote down.
4. If a stop has gone blurry, rebuild its scene from the paper copy that day.

Never rehearse by typing your words into a phone, a computer or a website.

We will never ask for a seed word or a passphrase. Never type one into this site or any tool it links to.