Calorie Calculator - Daily Caloric Needs

Could someone please put in their stats and see if they get "correct" results of caloric needs? I'm 5'8, 173lbs, 21 yrs old, and I do HIIT 25 mins/5 days a week. This calculator told me for fat loss I need 1884 cals/day, and for "extreme fat loss" (whatever that is), I need 1413 calories.

I've been told that with my stats, 1400 calories/day (what I was eating before) is way too low. For weight loss while keeping lean muscle, I've heard I should be instead eating around 2100-2300. I don't know why the website would give the option of extreme fat loss and fat loss, and not clarify what each means exactly, when obviously most people trying to lose weight would like to see results faster (if possible). This website is making it seem possible, but from what I've been learning, that number is not safe (for me).

Please give me your thoughts...

Honestly I would not use an online calculator. You simply cannot know what calculations they've used to create their program or how accurate it is.

I base all my calorie calculations on this:
Start with a figure of 14-16 calories per pound of bodyweight for *maintenance* for a moderately active adult.
Multiple that by 70% to get your weight loss calories.

That gives you a number that comes very close to the Harris Benedict equation.

At 173 lbs, that gives you 1816 calories for reasonable and safe weight loss. (173 * 15 * .7)

Awesome! Thank you so much. That's the first calculation that I feel like I can actually work with and continue to work with as I lose weight.