APRIL 21
Seed Words
The Words That Rebuild Your Keys
The Signal
Seed words turn enormous randomness into a short list of words that can rebuild your wallet’s keys.
The Reading
Imagine writing down 24 words. Together, they can hold the map to your Bitcoin wallet. This list is called a seed phrase, or recovery phrase. It is more than a password because it can rebuild the keys your wallet uses.
The real security is not in the words themselves. It begins before the words appear. A secure wallet starts with randomness. Bitcoiners call this entropy. With a 24-word BIP39 seed phrase, the wallet starts with 256 bits of entropy. That creates an unimaginably large number of possible starting patterns. The wallet turns that randomness into words that humans can write down and keep.
What if the wallet chose from only a tiny pool of possibilities? The 24 words might still look random, but an attacker could keep trying that smaller pool until the right one appeared. That is why good randomness matters. The words are the readable form. The entropy underneath is the fortress.
Guessing a correctly generated seed phrase is beyond practical reach. A 24-word BIP39 phrase has: 115,792,089,237,316,195,423,570,985,008,687,907,853,269,984,665,640, 564,039,457,584,007,913,129,639,936 possible combinations. Imagine a lottery with that many tickets and only one winner. An attacker must find your one correct phrase among them. If you want to remove reliance on a wallet manufacturer’s random-number generator, you can create entropy yourself using casino-grade dice and a proven unbiased conversion method. For example, 100 rolls of two dice provide more than enough raw randomness. Its fun and done correctly, you generate the entropy yourself rather than trusting someone else to generate it for you.
The seed phrase can recreate the wallet’s keys. Those keys let you authorise spending of bitcoin recorded on the Bitcoin network. The bitcoin is not inside the words. The words can rebuild the keys that control it. That is why seed words must be created securely and kept secret.
First Principles
A seed phrase is a human-readable way to rebuild wallet keys.
Entropy means randomness. Strong entropy creates an enormous number of possible seeds.
Someone who can recreate your wallet’s keys may be able to spend the bitcoin they control.
Today’s Challenge
Take a packet of dry beans and mark one bean with a small dot.
Put it into a cup with ten other beans and mix them. Finding it should be easy.
Now put it into the packet and mix again. The same bean is harder to find because the pool is bigger. Now imagine the packet becoming a room, then a stadium, then the universe. That growing pool is the idea behind entropy. Strong randomness makes the pool of possible seed phrases unimaginably large.
Tomorrow’s Signal
Not Your Keys, Not Your Coins