# openSSL ECDH private key size

When you are using a named curve like P-256 in openSSL, is there any standard key size for ECDH private key keys?

If you look at the ec_key.c file in the openSSL source this is what you see:

BN_rand_range(priv_key, order)


Here a cryptographically strong random number is generated which is smaller than the order.

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