These words describe things that are possible to do.
If something isachievable, it is possible to achieve it.
Make sure your weight-loss goals are achievable.
You can also say in formal language that a particular goal isattainable.
Employees benefit from having attainable goals.
The opposite ofattainableisunattainable.Unattainableis also formal.
Sometimes it feels like financial success is unattainable.
If something can be done, it isdoable.Feasiblehas a similar meaning but is more formal thandoableand is more commonly used in writing.
It's a big ask, but it's doable.
Given the lack of funding, is this plan really feasible?
The opposite offeasibleisunfeasible.
Your plan for growth is unfeasible.
A plan or method that can work isviable.
You have three weeks to come up with a viable plan.
The opposite ofviableisunviable.
The project is economically unviable.