I had 3 at the old house and gave them all away before the move.
So I’m now shopping for a new one.
Compost is mix of pulled weeds, some grass clippings & some kitchen waste including coffee grounds.
Look at the Orange or Blue big box store & see which of these might work.
Cheapest - Spading Fork - short handle.
Most Expensive - 10-tine Bedding Fork - may hold more than you want to lift.
In Between - 5-tine Manure Fork.
I use a both a 5 tine and a smaller 4 tine for heavier spots. The short handled spades are OK but require bending over. I’m kinda ancient so the 4 tine is the best for me.
When you say tine do you mean the thin ones or the thick somewhat wide ones.
I recall the thin tines were general for hay/straw.
I’m leaning towards a four thicker tine fork.
Generally my yards until this one were always huge, so I just built many compost piles and never turned them until I needed soil. Then I used a spade to break it up and load the wheelbarrow.
If all you are buying it for is turning compost, you might want to find one that serves other purposes, as well. You never know when you might need to run off a salesman caught with your daughter in the hayloft or find yourself roped into a monster posse or…
Now there the hay-fork seems like a better choice. Those fine tines seem more weaponized.
I gave away my good axe recently and my big chainsaw about 5 years ago. My baseball bats, pickaxe and bows also departed before the move. My maul would exhaust me these days.
I’m probably down to a Clue by 4, a good strong crowbar or a handy sharp edged flat garden spade.
I saw that as “the best style pitchpipe for tuning a compost pile”. Well, Zappa played a bicycle…
You aren’t alone. i was mildly amused and confused at the same time 
I thought it was about the right kind of tuning fork for a compost pile. Answer : none
Pitchfork… I’d probably go with a 5 tine long handled manure fork. The digging forks are strong, but short, hard to lift things with it. That 10 tine thing is WAY too big, compost is heavy. You still need to be cautious about trying to lift too much, but that’s the way I’d go.
The best is the one that someone else is using.
IME, you’ll be best served by a hayfork/compost fork with 4 or five thin tines. You don’t want a spading fork, the kind with wide tines. Those are made for breaking soil up, but you may have a harder time getting those thick tines into your pile easily.
Or…posing for an awful portrait 
(Get a Razor back, one with the handle)
This is the correct answer. 
Avoid the fiberglass ones. Or get a good pair of gloves.