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BlackCloudTools
24 calculators & converters. Always free.
Math
6 toolsPythagorean Theorem Calculator
Calculate any side of a right triangle using the Pythagorean theorem. Solve for hypotenuse, base, or height instantly.
a² + b² = c²📊Mean Median Mode Calculator
Calculate mean, median, mode, range, and standard deviation from any set of numbers. Free statistics calculator.
Mean = Σx / n√Square Root Calculator
Calculate square roots, cube roots, and nth roots. Shows simplified radical form (e.g. 6√2) and detects perfect squares.
√n = coefficient√radicand🔷Surface Area Calculator
Calculate surface area of 6 shapes: sphere, cube, cylinder, cone, rectangular prism, and square pyramid. Step-by-step solutions.
Sphere: 4πr²½Decimal to Fraction Converter
Convert any decimal to a simplified fraction in lowest terms. Shows mixed number, GCD steps, and fraction check.
n / 10^(decimal places) → simplify by GCD🎂Age Calculator
Calculate exact age between two dates. Shows years, months, days, total weeks, hours, and next birthday countdown.
targetDate − birthDateConverters
5 toolsWeight Converter
Convert weight between kilograms, pounds, ounces, grams, milligrams, metric tons, and stone. NIST-exact conversion factors.
Convert between metric and imperial units🌡️Temperature Converter
Convert temperature between Celsius, Fahrenheit, Kelvin, and Rankine. Instant, accurate temperature unit converter.
°F = (°C × 9/5) + 32📐Length Converter
Convert length between 9 units: millimeters, centimeters, meters, kilometers, inches, feet, yards, miles, and nautical miles. NIST-exact.
All units → meters → target unit🚀Speed Converter
Convert speed between mph, km/h, m/s, knots, and feet per second. Instant speed unit converter with all common units.
All units → m/s → target unit🧪Volume Converter
Convert volume between liters, milliliters, gallons, quarts, pints, cups, fluid ounces, and cubic meters. Metric and imperial.
All units → liters → target unitFinance
7 toolsSimple Interest Calculator
Calculate simple interest on loans and investments. Shows total amount, daily, and monthly interest breakdown.
SI = (P × R × T) / 100📈Compound Interest Calculator
Calculate compound interest with all compounding frequencies. Includes contributions, APY, and year-by-year growth table.
A = P(1 + r/n)^(nt)％Percentage Calculator
Calculate percentages in 4 modes: X% of Y, X is what % of Y, percentage change, and percentage difference.
(X / Y) × 100🏷️Discount Calculator
Calculate sale price after discount. Find discount amount, final price, and savings instantly. Supports any percentage.
Final = Original × (1 - Discount%/100)🍽️Tip Calculator
Calculate tip amount and split the bill among multiple people. Supports custom tip percentages and any number of guests.
Tip = Bill × Tip% / 100💼Gratuity Calculator
Calculate gratuity payout under the Payment of Gratuity Act 1972. Shows tax exemption up to ₹20 lakh and eligibility check.
(Salary × 15 × Years) / 26🏦Recurring Deposit Calculator
Calculate RD maturity amount with quarterly compounding. Month-by-month breakdown showing exact interest earned each quarter.
Quarterly compounding per RBI guidelinesHealth
4 toolsBMI Calculator
Calculate your BMI (Body Mass Index) with our free online tool. Includes WHO categories, health recommendations, and metric/imperial support.
BMI = weight (kg) / height (m)²💧Water Intake Calculator
Calculate daily water intake based on weight, activity level, exercise, and climate. Shows glasses and bottles needed.
30–44 ml per kg by activity level💪Protein Calculator
Calculate daily protein needs based on body weight and activity level. Based on WHO RDA 0.8 g/kg up to 2.2 g/kg for bodybuilders.
Protein (g) = weight (kg) × factor📏Waist to Hip Ratio Calculator
Calculate your waist-to-hip ratio (WHR) and check cardiovascular risk using WHO standards. Supports cm and inches.
WHR = waist ÷ hipText
2 toolsCharacter Counter
Count characters, words, lines, spaces, and paragraphs in real time. Includes social media character limits for Twitter, Instagram, and LinkedIn.
Text Case Converter
Convert text to camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE, Title Case, Sentence case, UPPER, and lower. One-click copy.