School of Rich Programmers

How to create your own Bitcoin mini-key?

Three strict but fair rules:

✔ 1. The first letter is always S

✔ 2. Only characters from the Base58 alphabet:

23456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz

✔ 3. Check: a key is only real if adding a "?" to the end makes the result start with two zeros.

For example, take the first key "S2R" and add a "?" to check it: "S2R?".

If you paste "S2R?" into the first task of the course,, you get a result starting with two zeros: 0052dae758c12..... This means that without the question mark, it is the correct key, which starts like this: 7e516f9523....

Other examples, ranging from 3-character to 32-character mini-keys, can be found here: Casascius-Ethereum.htm

Full list of 3-digit Casascius mini-keys existing in nature:

"S2R", "S3E", "S4Y", "SBe",
"SBy", "SC7", "SJi", "SLS",
"SaA", "Saq", "Sbq", "Scz",
"Sd7", "SgB", "SiU", "SkE"

Each of these 16 short keys passes the test because adding a "?" makes the result start with 00. But since they are only 3 characters long (instead of 22 or 30), their security is zero. Never use them for real money - any computer will crack these keys in less than a second.

For more examples, see: Casascius-Hologram.htm

How to create MiniKey: Casascius-Generator.htm

For Examples: Casascius-Ethereum.htm

Create: Minikey-to-Ethereum.htm

Create: Minikey-to-Bitcoin.htm