The fastest way to convert, calculate, format, and understand everyday numbers.
Fast browser-only converters, calculators, and formatting utilities. Each tool page includes formula notes, examples, and FAQs, with no fake placeholder pages in the index.
Live tools
cm to inches
Convert centimeters to inches using the exact 1 inch = 2.54 centimeters definition.
inches to cm
Convert inches to centimeters using the exact 1 inch = 2.54 centimeters definition.
kg to lbs
Convert kilograms to pounds using the exact definition 1 pound = 0.45359237 kilograms.
lbs to kg
Convert pounds to kilograms using the exact factor 1 pound = 0.45359237 kilograms.
C to F
Convert Celsius to Fahrenheit using the exact formula F = C x 9/5 + 32.
F to C
Convert Fahrenheit to Celsius using the exact formula C = (F - 32) x 5/9.
km to miles
Convert kilometers to miles using the exact relation 1 mile = 1.609344 kilometers.
miles to km
Convert miles to kilometers using the exact relation 1 mile = 1.609344 kilometers.
liters to gallons
Convert liters to US gallons using the exact relation 1 US gallon = 3.785411784 liters.
gallons to liters
Convert US gallons to liters using the exact relation 1 US gallon = 3.785411784 liters.
GST calculator
Add or remove GST at standard India rates with transparent base, tax, and total breakdown.
percentage calculator
Calculate percent of a number, percentage share, and percentage change in one page.
age calculator
Calculate exact age in years, months, and days between birth date and a target date.
word counter
Count words, characters, sentences, and paragraphs instantly in your browser.
JSON formatter
Format, minify, and validate JSON directly in your browser with instant error messages.
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We only index tools that are functional and tested. Conversion constants are explicit in source code, calculations run in your browser, and each page explains the formula behind the output.
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