🎲 Bitcoin Improvement Proposal 39 (BIP-39) Generator
BIP-39 Mnemonic Seed Phrase Generator
Generate 12-word (128-bit) and 24-word (256-bit) cryptographic recovery phrases using operating system hardware entropy with 100% in-browser privacy.
12-Word Recovery Mnemonic
Raw Entropy (Hex):
Checksum Verification:
Valid SHA-256 Checksum
⚠️ Security Advisory: Never store cryptocurrency recovery phrases on cloud clipboards or unencrypted digital documents.
How BIP-39 Seed Phrases Work
- Entropy to Bits: 12 words require $128\text{ bits}$ of entropy $+ 4\text{ checksum bits} = 132\text{ bits}$.
- 11-Bit Chunks: $132\text{ bits} \div 11\text{ bits/chunk} = 12\text{ words}$. Each 11-bit integer ($0$ to $2047$) points to an exact word in the standardized 2048-word dictionary.