the balance in genesis file is it in ether or wei?

Question

In genesis.json file I have this balance :

 "bd7a14e103ffa97ec5fd96d9975adb1b52756ef3": {
      "balance": "0x200000000000000000000000000000000000000000000000000000000000000"
    }

the hex number is the balance but does the value of ether or wei ?

Answer 1

Everything is in wei.

For a source that supports this assertion specifically for genesis files, have a look in genesis.go.

// GenesisBlockForTesting creates and writes a block in which addr has the given wei balance.
func GenesisBlockForTesting(db ethdb.Database, addr common.Address, balance *big.Int) *types.Block {
    g := Genesis{Alloc: GenesisAlloc{addr: {Balance: balance}}}
    return g.MustCommit(db)
}