Open Calculator

Every calculator is an equation you can flip.

Tap ? on any number to make it the unknown. Not sure of a number? Type a range like 70k~90k and the answer comes back as a 90% band.

Tip and split

each = bill x (1 + tip / 100) / people

A $87.50 bill with a 18% tip, split 3 ways, is $34.42 each

Take-home pay

net = gross - federal(gross, filing) - FICA(gross) - state(gross, state), per paycheck

$65,000 a year in Texas, single, paid every two weeks, takes home $2,092.60 per paycheck

Compound growth

A = P(1 + r/n)^(nt) + contributions, compounded monthly

$10,000 at 7% for 10 years, adding $200 a month, grows to $54,714

Final exam

target = current x (1 - w) + needed x w

With 85% now and a final worth 40%, a 97.5% on the final gives 90% overall

Hourly to salary

annual = hourly x hours x 52

$25.00 an hour, 40 hours a week, is $52,000 a year