[lokar]

Make sure you factor in extra taxes, in addition to the premium for being a contractor (that on its own should be at least 20%)

[jacquesm]

And the risk of being canned overnight, of receiving no severance pay, on being unable to collect on your bills in case things end up going South, not being paid when you get ill and so on. 50% is more like it.

Contractors charge more than employees for a reason.