Ice bath temperature is the number everyone asks for and the one with the least agreement behind it. The research protocols cluster in a fairly narrow band, colder is not shown to be better, and the practical question for a buyer is how you hold whatever temperature you choose without hauling ice every day.
The range in the literature
Studies on cold water immersion for recovery mostly sit between the high forties and the low sixties Fahrenheit. That is a wide band, and within it the evidence does not separate one temperature as better. What it does show is that colder water shortens how long you can stay in, so time and temperature trade against each other rather than stacking.
Choosing your own number
Start warmer than you think and go down over weeks. Most people who keep it up settle somewhere in the low fifties, which is cold enough to be a real stimulus and warm enough that a few minutes is achievable. Chasing a lower number for its own sake makes sessions shorter and the habit harder to keep.
Holding it with ice
Ice is how most people start and it is the reason most people stop. An uninsulated tub in warm weather can need a large quantity daily. Insulation is the single change that cuts it most, followed by a well fitted cover. If you are buying ice more than twice a week, the chiller is paying for itself in errands as much as money.
Holding it with a chiller
A chiller pulls the water down and holds a set point, usually with filtration and circulation in the same unit. Match its capacity to the water volume and to how warm your space gets, because an undersized unit runs continuously and never quite arrives. Chillers are rated for a pull-down rate, and that figure is the one to compare.
Questions people ask about ice bath temperature
How cold should an ice bath be?
The research clusters between the high forties and low sixties Fahrenheit. Most regular users settle in the low fifties.
Is colder better?
Not on the evidence. Colder shortens how long you can safely stay in, so the total exposure does not necessarily increase.
How much ice does it take?
More than expected in an uninsulated tub in warm weather. Insulation and a good cover cut it more than anything else.