know somebody/something inside out
US /noʊ ˈsʌm.bə.di ˈsʌm.θɪŋ ˌɪn.saɪd ˈaʊt/
UK /noʊ ˈsʌm.bə.di ˈsʌm.θɪŋ ˌɪn.saɪd ˈaʊt/

1.
tahu luar dalam, sangat mengenal
to know someone or something extremely well
:
•
She's worked here for twenty years, so she knows the company inside out.
Dia sudah bekerja di sini selama dua puluh tahun, jadi dia tahu perusahaan luar dalam.
•
He's a local, so he knows this area inside out.
Dia penduduk lokal, jadi dia tahu daerah ini luar dalam.