Hello,
I want to create child bitcoin address. (for payment)
How to i create payment address with php -no javascript-
Bitcoin wallets are just pairs of private/public keys. Your "password" is your private key, and your "address" for receiving currency is your public key. So to protect my privacy and security, i will use distinct addresses for each transaction. Nonetheless, the number of keys we have to carry around would keep increasing to the point that it just wouldn’t be practical. Again, that's reason why the HD wallets were introduced.
Try something like this codes below, it will be your best of friend on this one.
https://gist.githubusercontent.com/gunar/86c05f67e2a862f148bda1fc4f0a82f3/raw/8456458b11f72289519ef581560f06c3caf7b798/p2pkhFromXpub.js