"What does my salary work out to per hour?" seems like simple division, but the answer depends entirely on an assumption most quick mental-math skips: how many hours you actually work.
Convert annual salary to hourly, the standard assumption
At a standard 8 hours/day, 5 days/week schedule (2,080 hours/year), an $80,000 annual salary converts to $38.4615/hour, $307.69/day, and $1,538.46/week. This is the default most calculators (and this one) use — but it's an assumption, not a universal constant.
Hourly to salary calculator, why the assumption matters
Change the hours-per-week input to 35 instead of 40, and the same $80,000 salary works out to a noticeably higher hourly rate, because the same annual pay is spread across fewer hours. This is exactly why comparing a "$40/hour" contract offer to a "$80,000/year" salary offer requires knowing the actual hours behind each number.
Biweekly pay calculator, one input feeding every frequency
Enter pay at any single frequency — hourly, weekly, monthly, whatever your offer letter or paystub shows — and this tool converts it to all the others at once, including biweekly and semi-monthly, which are easy to mix up (biweekly is every 2 weeks, 26 times a year; semi-monthly is twice a month, 24 times a year).