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Calculate percentage, ratio, and growth rate instantly
Convert units across 7 categories: length, weight, temperature, area, volume, speed, data
Compare equal payment vs equal principal mortgage plans
Real-time exchange rates for 30+ currencies from ECB and open APIs
Calculate BMI with Chinese standard weight classification
Web calculator with arithmetic, parentheses, percentage, keyboard support
Calculate exact age, days to next birthday, zodiac and Chinese zodiac
Convert between binary, octal, decimal, hex, and base 2-36 with BigInt
Calculate days between dates or add/subtract N days from a date