A short companion for BIP39 Mnemonic: when it is useful, what it expects, and what to check before using the result.
What it does
Generate a BIP-39 mnemonic phrase from a chosen word count and derive the seed from it, which is how a cryptocurrency wallet backs up a key as words. It also checks a phrase you were given for a valid checksum.
Use the tool
Open BIP39 Mnemonic, add the input the tool asks for, run it, and check the output before using it elsewhere.
Input and output
- Input: text.
- Output: text.
- Category: Crypto.
Privacy and processing
Processing happens locally in your browser. This tool does not upload the input to ilham.dev.
Questions
Is it safe to generate a wallet seed in a browser?
The entropy comes from crypto.getRandomValues, so the randomness is real. The risk is the page and the machine, not the maths. For anything holding real value, generate offline on a machine you control.
Why does it reject my phrase?
The last word carries a checksum. If one word was mistyped the checksum fails and the phrase is rejected, which is the feature working as intended.
Related guide
For broader background, see Security and Cryptography Basics for Developers.