Verification tool
Check entropy is correctly applied.
Enter the same test entropy in this tool and another device or implementation, then compare their disposable BIP39 output.
Built on Ian Coleman’s open-source Mnemonic Code Converter and its calculation engine. Seed Tester inherits its MIT License.
Step 1 of 2
How many words?
Choose the test-output length you want to compare.
Step 2 of 2
Add your randomness.
Type or paste coin flips as 0 and 1, dice rolls as 1–6, decimal digits, or hexadecimal characters.
Enter digits or hexadecimal A–F. Spaces and punctuation are ignored.
Expected test output
Compare these words.
Compare every numbered word with the output from the other device or implementation. An exact match is evidence that both processed this entropy equivalently.
How did this input become these words?
Your input
The numbers were interpreted
A repeatable digital result was made
Converted sequence → repeatable digital resultThe result was mapped to words
Show technical details
--------Derived from the test words above with no passphrase.
For separate passphrase-derivation tests only. It does not change the words above and does not help verify entropy-to-word conversion. Never enter a passphrase used by a funded wallet.
Enter a test passphrase to estimate its resistance to offline guessing.
This is an estimate, not a guarantee. The scale is intentionally conservative for Bitcoin, assumes the seed words are already known, and reaches full at an estimated 100 bits.
--------This fingerprint is derived from the combination of the test seed words and the passphrase entered above. Changing either one is expected to produce a different wallet identity.
Because these phrases were entered online, discard both test phrases. Never retain, import, or fund them.
Download a standalone comparison copy
View source code on GitHub
The downloaded version is also test-only and must never be used to create a funded wallet.