I have been doing freelancing since last 2 years. When I started My hourly rate was $5 , After 6 months I have increased to $10. Now 2 years completed and I have successfully completed 60 projects , 1700+ hours and have TOP RATED badge.
So Should I increase my hourly rate to $15/$20? I would like to know what is base which help to decide hourly rate up down.
I have fear that high hourly rate could reduce work/project consistency.
It's up to you and there is no concrete answer to this question. Yes, you may be working for cheap money for months, but it could also be that $10 per hour is the top for your quality/expertise. You will never know if you don't try to increase.
Put all calcs on the paper. Would you earn more money working for one rate or another? If you will earn equally working 30% less time (and you can find clients for such rate), then go for it.
Increasing rate does not always mean that you want to earn more money. It also means that you want to earn the SAME but to work LESS.
First, there is certainly no universal answer to this. There are many factors, and a fair amount of them have little to do with your work itself, and more to do with your goals, tolerance to risk, etc.
I have fear that high hourly rate could reduce work/project consistency.
I think in your case, that's your answer. Since you're billing hourly (which is what I do), you can look at it as supply / demand.
When should you increase your price? When there is more demand than supply. Which is to say, when you turn down or delay new work because your schedule is full.
At that point your rate becomes a way to reduce demand until it matches the available supply. So if you're currently working at capacity, this method would have you increasing your rate incrementally until you reach a point of equilibrium.
Of course, freelancing is a bit volatile by nature, so 'equilibrium' won't really mean you never have to delay a new project or have some downtime between projects.
But supply / demand isn't a perfect model (at all) when it comes to your time. As Peter points out you could benefit from increasing your rate to a point that you have more time (supply) than work (demand) yet be making the same or more. I touch on this briefly during the 'I Don't Scale' section of my 'Adventures' talk.
Another factor to consider when it comes to hourly rates is that some clients won't be interested in you because of your rate. But that cuts both ways. It's not just clients that can't (or won't) afford higher rates, there are also clients that won't be interested in low rates because of what a low rate communicates to them.
You can raise rates without surplus demand as long as the value of your time has increased. Or, to state it another way, as long as you understand clients will have a different expectation when paying $50/hr than they do when paying $10/hr. (At least good, competent clients will.)
I would like to know what is base which help to decide hourly rate up down.
Not the only list that could be put together, but a tl;dr; of the above:
