なきゃいけない
Meanings
1
cannot do without; indispensable; absolutely necessary
usually written using kana alone
Expresses that something is essential or that one cannot manage without it. Often used with a noun marked by が or は.
See also: なくてはいけない
Experience is absolutely necessary for this job.
You can't get by without money.
2
usually written using kana alone
Attaches to the negative base (ない-stem) of a verb to express obligation or necessity. Equivalent to ~なければいけない, but more colloquial.
See also: なくてはいけない
I have to submit the report by tomorrow.
It's time I must go.