I think 20 hours per week is enough to make best productivity instead of letting them for long hours for all day.
Please let me know your opinion. Thanks in advance.
"Productive" has many different definitions. I think, as a rule of thumb... you need to be interested in what you're producing, even if it's just the code you're writing and not the end product itself.
I work 40 hours week, put in between 30-32 hours of design and development - and then go home to work on personal projects (which I do on the weekend, as well.) Atul was pretty spot-on with his estimate (hshno.de/ByT4UKjae).
It's also important to remember that working towards a goal without counting the hours is an art form within itself.
Putting an hourly value on being productive is like applying a soap-to-glass ratio when cleaning a dish. You just do it to the best of your ability, and make sure that the end result is clean - and, something you don't look back on with disappointment.
Atul Sharma
Full Stack Developer | Cloud Native Applications
I usually write new code/ solve bugs / do other code related tasks for almost 6-7 hrs a day .. Means 6*5 = 30 hrs (Office Hours).
Apart from Office work if you are working on some side projects, then you will easily end up coding from 7-8 hours daily on weekends .. or 1-2 hours roughly on weekdays.. 1 x 5 + 8 x 2 = 21 Hrs
So, roughly 51 productive hours a week.
I think it depends on person to person. You can easily code for at-least 6 productive hours daily.. which accounts to 30 hours, 5 days a week..