Why four letters per word are enough
The BIP39 English word list was designed so that the first four letters of every word are unique. โabstโ can only be โabstractโ, โzooโ only โzooโ. Stamping four letters per word cuts the work for a 24-word phrase from up to 192 letters to 96 and fits on smaller plates, and every wallet accepts the full words you rebuild from them. Our BIP39 word list tool confirms which word a 4-letter prefix belongs to โ check one word at a time, never the whole phrase.
If you prefer full words for readability, choose โFull wordโ: the planner then counts the worst case of 8 letters per word.
Copies, splits, multisig or SLIP-39?
The planner compares the main ways to protect against both loss and theft:
- One backup โ simplest, but a single fire, flood or burglary ends it.
- Identical copies in different places โ survives losing all but one copy, but each location alone is enough for a thief.
- Splitting one phrase into parts โ a trap: losing any part loses everything, and a stolen half of a 12-word phrase leaves only about 62 bits of security.
- Multisig (for example 2-of-3 wallets) โ each key has its own full backup; any two recover the funds, one stolen key is useless.
- Shamir backup, SLIP-39 (for example 2-of-3 shares) โ similar protection from a single wallet, but the shares are 20 or 33 words and need a wallet that supports SLIP-39.
The results show how many pieces you can lose without losing funds and how many a thief needs. A good plan has at least 1 for the first and at least 2 for the second.
Example: 24 words, two copies
A 24-word phrase stamped with 4 letters per word is 96 letters per copy. Two copies mean 192 letters and two plates that each hold 24 words. At about 30 seconds per letter, including alignment and checking, that is roughly 96 minutes of stamping. With a BIP39 passphrase, add a third plate stored in a different place. Switching to a 2-of-3 multisig instead triples the stamping but means one stolen plate is no longer enough to take the funds.
Doing it safely
- Work offline: write the words by hand on the printed worksheet, never type them into a phone or computer.
- Stamp in a private place, then verify every word against the walletโs display before destroying the paper.
- Test the backup: restore the wallet on a spare device or check that the restored wallet shows the same receiving address.
- Label plates with a neutral code, not โBITCOIN SEEDโ.
- Store the passphrase separately from the phrase it protects.
- Record in your inheritance plan where plates are and how many are needed โ not what is on them.
Frequently asked questions
+Do I enter my seed phrase into this planner?
No, never. The planner uses only counts โ words, copies, plates โ and the printable worksheet is blank. Do not type a seed phrase into any website.
+Is stamping only 4 letters per BIP39 word safe?
Yes for the English BIP39 list: the first four letters of every word are unique, so the full phrase can be rebuilt exactly. Words with only three letters are stamped as they are.
+How many metal backups should I make?
At least two in different locations, or use a scheme like 2-of-3 multisig or SLIP-39 so that you can lose one piece and a thief needs more than one.
+Should I split my seed phrase in half?
No. Splitting creates two single points of failure and leaks part of the secret. Use multisig or SLIP-39 if you want to distribute a backup.
+Is the worksheet free to download?
Yes โ print it from the page or download the Word file above. No sign-up and no e-mail.
+Can I download the template for free without registration?
Yes. The Word (.docx) file is a direct link on this page: no account, no e-mail and no payment. You can also use the online version above and export your own numbers.
Calculations run entirely in your browser; nothing you type is sent to KOT.CASH. Results are estimates for information only and are not financial, tax or legal advice.