Freelance developer day rate: how to work out what to charge

Developer day rates vary widely by stack, seniority and whether you are delivering or advising. Working back from the take-home you want is the way to find your own number rather than copying a forum figure that was set for someone else's costs.

Work backwards from the take-home you want

Decide what you want to end the year with in your account, after tax. That is the figure everything else in the sum protects.

Add back tax and National Insurance

You need to earn enough that your target take-home is what is left once tax and National Insurance come out. The gross figure depends on your total income and allowances, so work it out with an accountant or from your tax authority's guidance. That gross number, not the take-home, is what the rest of the calculation uses.

Add your real business costs

Software, insurance, equipment, an accountant, a share of your workspace, the time spent finding the next contract. These come out before any of the money is yours.

Divide by the days you can honestly bill

Build time is billable; the time spent on estimates, code review of your own work, keeping skills current and unpaid discovery calls is not. Most solo developers land between 150 and 190 billable days.

Take your working days in the year and subtract holiday, sick days, admin, quoting, marketing and the gaps between contracts. Divide your target by that smaller number, not by 260, or you have built a rate that only works in a year that does not exist.

Check the jobs you actually take

The rate is a floor. Once you are working, the question becomes whether the projects you quoted actually paid it. That is worth tracking job by job.

This is a planning method, not financial or tax advice. Check your own position with an accountant or your tax authority.