Why P247?

P247 stands for "percent 24/7" -- everyday math tools available around the clock. Whether you are figuring out a tip at dinner, comparing mortgage options, checking a BMI reading, or converting units for a recipe, the goal is the same: get the answer fast and move on with your life.

Every calculator on this site runs 100% in your browser. Your numbers stay on your device. There are no server requests, no databases, and no accounts. We built P247 because the other calculator sites out there are slow, full of ads that cover the screen, and track everything you do. This one does not.

How to Use These Calculators

Click any tool from the sidebar or the cards above. Enter your values and results appear instantly -- no "Calculate" button needed on most tools. Each calculator includes a detailed guide below the tool explaining the math, formulas, and practical tips so you actually understand what the numbers mean.

Built for Every Device

P247 works on phones, tablets, laptops, and desktops. The layout adapts to your screen size automatically. On mobile, tap the menu icon in the top-left corner to switch between calculators.