A browser-based application that helps recover lost BIP-39 seed phrase words by brute-forcing the missing words and finding valid combinations with correct checksums.
ONLY USE THIS TOOL ON AN OFFLINE, AIR-GAPPED COMPUTER!
- Never enter real seed phrases on an internet-connected device
- Your seed phrase controls your cryptocurrency assets
- This tool should only be used in a secure, offline environment
- Entering sensitive seed phrases on an online computer can lead to complete loss of funds
This tool helps you recover a complete 24-word BIP-39 seed phrase when you have most of the words but are missing a few. It:
- Takes your known seed words as input (less than 24 words)
- Generates all possible combinations to complete the phrase to 24 words
- Validates each combination using BIP-39 checksum verification
- Derives the first Ethereum address using the Ledger derivation path (
m/44'/60'/0'/0/0) - Displays all valid combinations with their corresponding addresses
- Download this repository and open
index.htmlin a modern web browser - Enter your known seed words in the text field (space or comma separated)
- Click "Recover Missing Words"
- Wait for the tool to find valid combinations
- Review the results showing complete phrases and derived addresses
The number of missing words affects both total combinations and valid results:
BIP-39 24-word phrases consist of:
- 256 bits of entropy (random data)
- 8 bits of checksum (derived from entropy via SHA-256)
- Total: 264 bits = 24 words Γ 11 bits each
The checksum dramatically reduces the search space:
-
1 missing word (11 bits):
- Total combinations: 2,048
- Valid phrases: ~8 (1 in 256, due to 8-bit checksum)
- Time: < 1 second
-
2 missing words (22 bits):
- Total combinations: 4,194,304
- Valid phrases: ~16,384 (2^14, because 8 bits are checksum)
- Time: Few seconds
-
3 missing words (33 bits):
- Total combinations: 8,589,934,592
- Valid phrases: ~33,554,432 (2^25)
- Time: Several minutes
-
4+ missing words: May take hours/days or crash your browser
Why the reduction? The 8-bit checksum must match the entropy. This eliminates 255 out of every 256 random combinations, significantly reducing valid results compared to total combinations tested.
- Make sure all entered words are spelled correctly
- Words should be from the standard BIP-39 English word list
- The tool validates words as you enter them
- You can stop the recovery process at any time using the "Stop" button
- Results are displayed as they are found
To test the tool without using real seed phrases, try this example:
Enter these 23 words:
abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon
The tool should find the valid completion with the 24th word.
- ethers.js v6: For BIP-39 mnemonic validation and HD wallet derivation
- Pure JavaScript: No build process required
- Client-side only: All processing happens in your browser
- Input Validation: Checks each word against the BIP-39 word list (2048 words)
- Combination Generation: Creates all possible completions using remaining words
- Checksum Validation: Uses BIP-39 checksum to verify valid mnemonics
- Address Derivation: Derives Ethereum address using Ledger Live path
- Real-time Results: Shows valid combinations as they are found
- Seed phrases use a specific list of 2048 words
- Each word represents 11 bits of entropy
- Last word contains checksum bits
- 24 words = 256 bits of entropy + 8-bit checksum
- Uses HD wallet derivation per BIP-44
- Ledger Live path:
m/44'/60'/0'/0/0 - Generates the first address from the derived wallet
- β Runs entirely in your browser
- β No network requests or external API calls
- β No data transmission
- β Prominent security warnings
- β Can be used offline
- Only supports 24-word seed phrases
- Only supports English BIP-39 word list
- Only derives Ethereum addresses (EVM compatible)
- Performance degrades exponentially with more missing words
- Browser may crash with 4+ missing words due to memory constraints
- Check spelling of each word
- Ensure words are from the BIP-39 word list
- Remove any extra spaces or punctuation
- You may have too many missing words
- Try stopping the process and reducing missing words
- Close other browser tabs to free up memory
- Verify that the entered words are correct
- Check that words are in the correct order
- The seed phrase may have errors in the known words
This is a single-file application for simplicity and security. The complete implementation is in index.html.
word-recoverer/
βββ index.html # Complete application
βββ README.md # This file
βββ plan.md # Implementation plan and specifications
Simply open index.html in any modern web browser. No server or build process needed.
For security testing, you can:
- Disconnect from the internet
- Open the file locally
- Test with known seed phrases
Q: Is this tool safe to use?
A: Only if used offline on an air-gapped computer. Never use it on an internet-connected device with real seed phrases.
Q: How long will recovery take?
A: Depends on missing words: 1 word = instant, 2 words = seconds, 3 words = minutes to hours.
Q: Can I recover passwords or passphrases?
A: No, this only recovers BIP-39 seed phrase words, not passwords.
Q: Will this work for Bitcoin or other cryptocurrencies?
A: The checksum validation works for any BIP-39 phrase, but address derivation is currently Ethereum-only.
Q: What if I have more than 3 missing words?
A: The tool will warn you and may take an extremely long time or crash. Consider if you have other information to narrow down possibilities.
This tool is provided as-is for educational and recovery purposes. Use at your own risk.
- This software is provided without warranty
- Always verify recovered addresses match your expected wallet
- Test with small amounts before using recovered seeds
- The authors are not responsible for any loss of funds
- This tool does not guarantee successful recovery
Remember: Your seed phrase is the master key to your cryptocurrency. Treat it with extreme care and only use this tool in a secure, offline environment.