I recently got a freezer and want to start cold crashing my beers before bottling but I’m having a hard time finding a straight answer as to what to enter into a priming calculator. Hopefully you guys can help
I don’t use a calculator. I just use a slightly scant 2/3 cup cane sugar per 5 gallons for 90% of my beers and ignore temperature. For what it’s worth, my bottling temperature is cellar temp / fermentation temp, typically in the 60s, but perhaps in the 50s for lagers. I usually don’t cold crash my beers unless I am experiencing a significant haze, and even then, I’ll use gelatin to knock that out if necessary, still in the 50s or 60s.
Your first option is the correct answer. But you only really need to adjust the sugar weight by the volume of beer your priming (assuming you let the beer fully ferment before cold-crashing).
The reason the carbonation calculators ask for fermentation temperature is because they calculate how much CO2 from fermentation is left in the beer when you go to bottle it. CO2 will come out of suspension in the beer if the existing concentration is too high for the beer temperature, but it won’t go back in if you later lower the temperature. So record the highest temperature the beer sees after fermentation ends, and use that.