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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.
Image
8 toolsImage Format Converter
Convert images between PNG, JPG, WebP, AVIF, and BMP for free, right in your browser. No upload, no sign-up, no watermark.
HEIC to JPG/PNG Converter
Convert iPhone HEIC/HEIF photos to JPG or PNG, free and instantly in your browser. No upload, no sign-up, no watermark.
Image Compressor
Compress JPG, PNG, and WebP images to a target file size in KB or MB, free and instantly in your browser. No upload required.
Image Resizer
Resize images to exact pixel dimensions or common presets like passport photo, LinkedIn, Instagram, and YouTube thumbnail. Free, in-browser.
SVG to PNG Converter
Convert SVG vector images to PNG or JPG at any resolution, free and instantly in your browser. No server upload.
Favicon Generator
Generate a multi-size favicon.ico file from any image or logo, free and instantly in your browser. Includes 16, 32, 48, 64, 128, and 256px sizes.
Image to Base64 Converter
Convert images to Base64 strings for embedding in CSS or HTML, or decode Base64 back into a downloadable image. Free, instant, in-browser.
Color Palette Extractor
Extract the dominant colors and a matching palette from any image, with hex and RGB values. Free tool for designers, runs entirely in-browser.
Data
3 toolsQR Code Generator
Generate free QR codes for URLs, plain text, WiFi networks, and contact cards (vCard). Download as PNG, no sign-up, no expiry.
CSV to JSON Converter
Convert CSV to JSON or JSON to CSV instantly in your browser. Handles quoted fields, commas, and headers correctly. Free, no upload.
XLSX to CSV Converter
Convert Excel (XLSX) spreadsheets to CSV or CSV to XLSX, free and instantly in your browser. Supports multi-sheet workbooks. No upload.
PDF Merge
Merge multiple PDF files into a single document, free and instantly in your browser. Reorder files before merging. No upload required.
PDF Split
Split a PDF into multiple files by page range, free and instantly in your browser. No upload, no sign-up.
PDF Rotate & Reorder
Rotate and reorder PDF pages by dragging them into place, free and instantly in your browser. No upload, no sign-up.
Images to PDF
Combine multiple images into a single PDF file, free and instantly in your browser. Supports JPG, PNG, WebP, and BMP. No upload required.
PDF to Image Converter
Convert every page of a PDF into a PNG or JPG image, free and instantly in your browser. No upload, no sign-up, no watermark.
PDF Compressor
Reduce PDF file size for free, right in your browser. Best for scanned or image-heavy PDFs. No upload, no sign-up.
Audio/Video
4 toolsVideo to Audio Converter
Extract the audio track from any video as MP3, WAV, AAC, or OGG, free and instantly in your browser. No upload, no sign-up.
Audio Format Converter
Convert audio files between MP3, WAV, and OGG, free and instantly in your browser. No upload, no sign-up.
Video Trimmer
Trim or cut a video to a specific start and end time, free and instantly in your browser. No upload, no sign-up, no watermark.
Video to GIF Converter
Convert a video clip to a high-quality animated GIF, free and instantly in your browser. No upload, no sign-up, no watermark.