Secure seed calculator

         Secure calculator is the one which works without the necessity of Internet connection. You can be sure that nobody will get your results only when the computer you work on is not connected to the Internet. To keep your seed 100% secure, you should carefully read THE SAFETY RULES before you act. No matter if you execute your own code, or use any third party software like the one offered here!
If you can not calculate the last checksum word by yourself, but you do care about the secureness, you can buy an offline tool licenced by
The tool you will get here is an application working in console mode, tested both on Windows and Linux. It calculates the last checksum word for any 24-element seed complying BIP39 standard. It implements exactly the same algorithm which works online on this website.
The licence price is  20 USDC
or an equivalent of 25$ paid by one of these 4 coins - BTC, ETH, DOT or ZEC.
To order the application, please contact at:

We accept cryptocurrency payments only.