About

Tools with the factor written down.

ProHacks is a free collection of utilities for people anywhere. The site is in English because the searches are global: centimetres to inches, HEIC to JPG, a mortgage payment, a GPA, a QR code.

What “exact” means here

The inch is 2.54 centimetres. The avoirdupois pound is 0.45359237 kilograms. The international mile is 1.609344 kilometres. The US liquid gallon is 3.785411784 litres. Those are definitions, and the converters use them. A US cup on this site is the customary 8-fluid-ounce cup, 236.5882365 millilitres, and the page says when a recipe means 240 or 250 instead.

Files stay put

Image and PDF tools run in the browser. A photo is not uploaded to make a JPEG, and a PDF is not uploaded to merge. Leave the page and the file is gone from the tool. Calculators work the same way: the number is used in the tab and not sent off as the calculation.

What the calculators are not

The mortgage figure is principal and interest for a fixed rate. It is not a loan offer, and it does not include tax or insurance. The GPA table is a common 4.0 / 4.3 scale, and your school’s own table wins if they differ. Compound interest assumes the rate you type never changes.

Questions and corrections: hello@prohacks.in. Read the privacy and terms pages before you rely on a result for anything formal.