Free Online Calculators & Smart Tools for Money, Math, Health and Everyday Life
Tipping in the United States confuses even Americans, because the expected amount changes with the setting, the service, and sometimes the city. In many service jobs, tips are not a bonus on top of a full wage — they are…
A raise sounds simple until you try to compare two offers or work out whether a new salary is actually better. A 3 percent raise on one salary and a 2 dollar hourly bump on another are hard to compare…
An emergency fund is money set aside for the costs you cannot plan for: a broken boiler, a car repair, a medical bill, or a sudden loss of income. It is not a holiday fund, a deposit fund or an…
Finding a place to live is exciting, but it also brings one of the biggest monthly financial decisions most people face: how much rent is actually sensible? Spend too much and everyday life feels squeezed. Spend too little, and you…
Health advice loves complicated tests, but one of the most useful numbers needs only a tape measure. Waist-to-height ratio divides your waist circumference by your height, and the result tells you whether belly fat is likely putting your health at…
Step on a scale, get a BMI number, and you are told whether you are healthy, overweight, or obese. It feels scientific, but it misses something important: BMI never looks at what your weight is made of. Two people can…
Body mass index, or BMI, is one number — weight relative to height — but its meaning shifts as you age. A BMI of 26 means something different at 28, when muscle is easy to keep, than at 68, when…
You spot a jacket marked down to $60 and wonder whether the deal is as good as the sticker claims. The tag shouts “25% off” but hides the one number that would let you judge: the price before the discount.…
Percentages are the math of everyday money — discounts, tips, raises, taxes — and they are also the math people get wrong most often, and most confidently. The mistakes below are not obscure edge cases. They show up at checkout…
A salary jumps from $60,000 to $66,000. One calculator calls that a 10% raise. Another says the two salaries differ by 9.52%. Both calculators are right, because they are answering different questions. Mixing up percentage increase and percentage difference is…