This question is better suited in the career/job advice forum.
How much money you can charge only partly depends on how much experience you have, it also depends on the quality you provide. I know that there is some kind of comparison chart somewhere on the internet but that can only be a ruogh guide as your local conditions are very specific. While a develoepr from India will work for $5 an hour a European or American wouldn’t even get out of bed for less than $20.
Also, what you charge depends on how complex the task/project is. If it’s a simple HTML/CSS job you’ll probably not charge $100 per hour while if it’s a big a** application that would be appropriate.
I can tell you how I’m doing it: My base rate is €30 per hour (I’m only a front-end developer and designer) and if people ask for a fixed price I’m estimating the time for a project and then calculate based on that hourly rate. Add 50% to what you have estimated/calculated (because many times you will underestimate a requirement, especially if you’re not so experienced) and that’s it. Then the small/medium/large project question is also covered.
I don’t quite know what other freelancers in my area are charging but I’ve learned from experience. You can usually charge more when working for big companies than for average Joe’s Diner website. When I had an offer for a job that I actually didn’t wanna do then I’ve raised my price just to see how they would react (because I wouldn’t have been sad if I didn’t get the job) and to my surprise sometimes they actually went with that price. Sometimes, however, people wouldn’t hire me, so that’s when it leveled out at €30 per hour for me – but I’m only good at HTML and CSS (and I know it) and a little bit JS. So you could probably charge around €40 (=$55) for such kind of work.
I guess as decent back-end programmer you can charge $50–$80 per hour, again, depending on the client and general economical state in the area where you are.
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