Depending on how often I turn it, and how active it gets, it can be done in 3 weeks.* Then it can go on the garden, or sit until I need it. ... *This is the "hot" method of composting. Yup, lots of labor, but sometimes I'm in a hurry for some compost.
Wow, 3 weeks is amazing, but if you put all that work into the turning of your hot compost piles, then you deserve the rewards. My strategy was to make more chicken run compost then I could use, so I always have compost in the run ready to harvest when needed. It took me about 6 months of adding material to the chicken run to get to the point where I now have more compost than I can use. I continue to add material to the chicken run all the time, but I'm never in a hurry to make compost as I have more than I can use.
Last year, I was giving away chicken run compost to my good neighbors for their raised beds. They loved it. And I still have more compost in the chicken run than I can use for myself.
Also, another pitch for my cement mixer compost sifter.... I can sift out 6 cubic feet (3 bags of compost) into my gorilla cart in about 15 minutes. The sifted compost goes to the garden and raised beds, and the unfinished compost gets thrown back into the chicken run. Anyway, I used to buy compost at $5 per bag at our big box stores, but now I can process compost from my chicken run at the rate of about $120 per hour (if I had to buy compost bags at the store). My days of needing compost in a hurry are behind me. I got years worth of compost ready to harvest in my chicken run.