Handy Dandy is a tool that helps visualize and work with data in different formats that are used in Bitcoin protocol such as private keys and mnemonics.
A potential use case is offline generation of private keys or mnemonics using a coin flip.
User selects what result they want to generate (eg. a 15-word BIP-39 mnemonic) by selecting the appropriate options on top of the window and the program automatically generates appropriate number of bits to be set. In this example it is 165 bits (160 bit entropy + 5 bit dynamically computed checksum).
Then the user has to flip a coin and set each bit. For example
Heads: 1
Tails: 0
Heads: 1
Heads: 1
As each bit is being set, the respective value is also printed as integer, hexadecimal and BIP-39 word.
After all bits were set the final result will be printed in the result TextBox at the bottom of the page and can be copied.
Source code and compiled binaries can be found here:
https://github.com/Coding-Enthusiast/HandyDandyThis project is in beta. Please report any bugs you find here or on GitHub
If You found this tool helpful consider making a donation:
Legacy address: 1Q9swRQuwhTtjZZ2yguFWk7m7pszknkWyk
SegWit address: bc1q3n5t9gv40ayq68nwf0yth49dt5c799wpld376s
The idea for project was influenced by:
https://bitcointalksearch.org/topic/bitcoin-visual-private-key-generator-5187401