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Projectile Motion Calculator New
Drag to aim a launch, then watch the arc fly. Change speed, angle, and gravity and see range, peak height, and time of flight update live. Physics Wave Speed Calculator New
Watch a travelling wave in real time and see how frequency and wavelength set its speed. Drag the wave, change any value, and explore v = f times lambda live. Physics Frequency and Period Calculator New
See how frequency and period are two views of one motion. Tap a beat or drag the slider and watch the period and angular frequency update live. Physics Pendulum Period Calculator New
Drag the bob and let it swing. Change length, angle, and gravity and watch the period, velocity, and potential-to-kinetic energy trade update live. Physics Heat Transfer Calculator New
Watch heat flow from a hot block to a cold one until they reach the same temperature. Drag a block to set its heat and see equilibrium happen live. Physics Ohm's Law Calculator New
See Ohm's law come alive. Set the voltage and resistance and watch the current, power, and charge flow update live in an interactive circuit. Physics Simple Harmonic Motion Calculator New
Watch simple harmonic motion live. Set the mass, spring constant, and amplitude and see the period, speed, and energy of a mass on a spring update instantly. Physics Ideal Gas Law Calculator New
See the ideal gas law come alive. Set the temperature, volume, and amount and watch the pressure and the gas particles respond through PV = nRT. Physics Momentum and Collision Calculator New
Collide two carts and watch conservation of momentum in action. Set the masses, speed, and restitution and compare elastic vs inelastic collisions live. Physics Inclined Plane Calculator New
Watch a block on a ramp slide or hold still. Set the angle, mass, and friction and see the force components and acceleration a = g(sinθ - μcosθ) live. Physics Doppler Effect Calculator New
See the Doppler effect in action. Move a source and watch its wavefronts bunch up ahead and stretch behind while the observed frequency shifts up and down. Physics Unit Circle Calculator New
Drag a point around an interactive unit circle. Watch sin, cos, and tan update live, see the reference triangle, and trace the sine wave in your browser. Applied Math Quadratic Equation Solver New
Solve ax² + bx + c = 0 visually. Slide the coefficients or drag the vertex and watch the roots, discriminant, and axis of symmetry update on a live parabola. Applied Math Probability Calculator New
Flip a coin or roll a die thousands of times and watch the empirical frequency converge on the theoretical probability. The law of large numbers, animated. Applied Math Age Calculator New
Calculate your exact age in years, months, and days from a date of birth, plus totals in months, weeks, and days and a countdown to your next birthday. Date & Time Aspect Ratio Calculator
Lock an aspect ratio like 16:9 and solve the missing width or height. Design & CSS Base64 Encoder & Decoder New
Encode and decode Base64 strings instantly in your browser. Fast, private, and free. Developer Utilities Binary Text Converter
Convert text to binary (0s and 1s) and binary back to text, instantly in your browser. No uploads. Developer Utilities BMI Calculator New
Calculate your Body Mass Index from height and weight, see your WHO category, and the healthy weight range for your height. Health & Fitness BMR Calculator New
Calculate your basal metabolic rate with the Mifflin-St Jeor equation, and see what each activity level adds on top of it. Health & Fitness Body Fat Calculator New
Estimate your body fat percentage with the U.S. Navy tape-measure method, plus your fat mass and lean mass, in metric or imperial. Health & Fitness Body Weight Tracker New
Log your weight each day and watch the trend line with a smoothed average and optional goal, all stored privately in your browser. Health & Fitness CAGR Calculator New
Calculate compound annual growth rate live from a starting value, ending value, and period, with total growth and doubling time. Money & Finance Calorie Deficit Calculator New
Work out what to eat a day for a chosen rate of weight loss, and how many weeks that rate takes to reach your goal weight. Health & Fitness camelCase Converter
Convert text to camelCase for variable and function names. Text Utilities Character Counter New
Count characters instantly in your browser. Includes characters with and without spaces. Text Utilities WCAG Color Contrast Checker
Check text and background colors against WCAG AA and AAA contrast. Design & CSS Color Format Converter
Convert colors between HEX, RGB, HSL, HSV, OKLCH, and CMYK instantly. Design & CSS Combinations & Permutations Calculator New
Compute nCr and nPr exactly, with or without repetition, with the formula expanded step by step and a plain-language reading of how many ways you can choose. Applied Math Compound Interest Calculator New
Calculate compound interest and see how savings or investments grow over time, with optional monthly contributions. Money & Finance CRC32 Hash Generator
Generate a CRC32 checksum from text instantly in your browser. A fast error-detection hash, not for security. Developer Utilities Cron Expression Parser New
Parse a cron expression into plain English, count how often it runs, and see next run times. Supports lists, ranges, steps, and month or weekday names. Date & Time CSV Cleaner New
Clean a messy CSV in one pass: remove empty rows, trim stray whitespace, fix trailing commas, and square up ragged rows. Developer Utilities CSV Diff New
Compare two CSV files in your browser and see which rows were added, removed, or changed, with per-column detail. Developer Utilities CSV to JSON Converter New
Convert CSV to a JSON array of objects for APIs, JavaScript, and databases. Smart type detection, custom delimiters, and RFC 4180 quoting. In-browser and free. Developer Utilities CSV to TSV Converter New
Convert comma-separated values to tab-separated values with quoting handled correctly, entirely in your browser. Developer Utilities Date Difference Calculator New
Count the exact time between two dates in years, months, and days, plus totals in days, weeks, and months and the number of weekdays (business days). Date & Time Discount Calculator New
Calculate the sale price and how much you save from a percentage or fixed-amount discount. Number Utilities Emergency Fund Calculator New
Work out how much emergency savings you need based on monthly expenses, and track your progress toward the target. Money & Finance Find and Replace New
Find and replace text instantly in your browser. Supports plain text and regex. Shows match count live. Nothing is uploaded. Text Utilities Fraction Calculator New
Add, subtract, multiply, or divide fractions and mixed numbers with every step shown: the LCD, the conversion, and simplifying, plus mixed and decimal forms. Applied Math Heart Rate Zone Calculator New
Find your maximum heart rate and five training zones from your age, with the Karvonen method when you add a resting heart rate. Health & Fitness Hex Encoder & Decoder New
Encode text to hexadecimal and decode hex back to readable text instantly in your browser. Fast, private, and free. Developer Utilities HTML Entity Encoder & Decoder New
Encode and decode HTML entities instantly in your browser. Fast, private, and free. Developer Utilities Ideal Weight Calculator New
Estimate your ideal body weight from height and sex with the Devine, Robinson, Miller, and Hamwi formulas, plus the modern BMI healthy range. Health & Fitness Inflation Calculator New
See what your money will be worth after inflation, how much purchasing power is lost, and the future cost of the same goods. Money & Finance JSON Escape / Unescape New
Escape text for use inside a JSON string, or unescape a JSON string literal back to plain text, live in your browser. Developer Utilities JSON Formatter New
Pretty-print and beautify JSON with proper indentation instantly in your browser. Fast, private, and free. Developer Utilities JSON Minifier New
Minify and compress JSON by removing whitespace instantly in your browser. Fast, private, and free. Developer Utilities JSON to CSV Converter New
Convert JSON arrays to CSV for spreadsheets, databases, and data analysis. Handles nested objects, sparse data, and special characters. Free and private. Developer Utilities JSON to YAML Converter New
Convert JSON to YAML for Kubernetes, Docker Compose, and CI/CD configs. Smart quoting, literal block scalars, and sort-key options. Private and in-browser. Developer Utilities JSON Tree Viewer New
Visualize JSON as a collapsible tree. Explore structure, search keys and values, and copy any node path or value. Fast, private, and free. Developer Utilities JSON Validator New
Validate JSON syntax and see errors instantly in your browser. Fast, private, and free. Developer Utilities JWT Decoder New
Decode a JSON Web Token to read its header, payload, and claims. 100% in your browser. Your token is never sent to a server. Developer Utilities kebab-case Converter
Convert text to kebab-case for CSS classes, URL slugs, and IDs. Text Utilities Keep Screen Awake New
Prevent your device from sleeping while this page remains open. Productivity Letter Counter New
Count only the letters in your text. Excludes digits, spaces, and punctuation. Runs instantly in your browser. Text Utilities Line Counter New
Count lines in your text instantly. Shows total lines, non-empty lines, paragraphs, and word count. Runs in your browser. Text Utilities Lorem Ipsum Generator New
Generate lorem ipsum placeholder text in your browser. Choose paragraphs, sentences, or words, set the count, and copy plain text. Nothing is uploaded. Generators Lowercase Converter
Convert any text to lowercase instantly in your browser — paste, convert, and copy with no uploads. Text Utilities Macro Calculator New
Split a daily calorie target into grams of protein, carbs, and fat with balanced, high-protein, low-carb, or keto presets. Health & Fitness Margin Calculator New
Calculate gross margin percentage, gross profit, and markup from cost and selling price. Number Utilities Markup Calculator
Find markup percentage from cost and selling price, or set a price from a target markup. Shows profit and margin too. Number Utilities MD5 Hash Generator New
Generate an MD5 hash from any text instantly in your browser. Fast, private, and free. Developer Utilities Move Today Tracker New
Tap once a day to log that you moved, build a streak, and watch a month of activity fill in. A dead-simple movement habit tracker. Health & Fitness Normalize Whitespace
Collapse all whitespace into single spaces and trim the result. Text Utilities Notepad New
Simple notes stored in your browser. Auto-saved, private, and free. Productivity One Rep Max Calculator New
Estimate your one rep max from a set you actually lifted, across four formulas, with the training percentages a program is written in. Health & Fitness Paragraph Counter New
Count paragraphs in any text instantly. Paragraphs are separated by blank lines. Text Utilities Password Generator New
Create strong, random passwords in your browser. Pick the length and character sets, see a live entropy and strength estimate, then copy. Nothing is uploaded. Generators Percentage Calculator
Calculate percentages, percentage change, and percentage of totals. Number Utilities Pomodoro Timer New
Use the Pomodoro Technique to stay focused with timed work sessions and breaks. Productivity Prime Factorization Calculator New
Factor any number into primes with the divisions narrated in exponent form, plus primality, divisor count, and GCF and LCM against an optional second number. Applied Math Protein Intake Calculator New
Find the protein range your body weight and training goal actually support, with the per-meal split and the grams-per-kilogram it came from. Health & Fitness Punycode Converter
Convert internationalized domain names between Unicode and Punycode (xn--) form, in your browser. Developer Utilities PX to DP Converter
Convert px to dp and sp across Android density buckets and iOS points. Design & CSS PX to REM Converter
Convert px to rem, em, and pt against a configurable root font size. Design & CSS QR Code Generator New
Create QR codes in your browser from text, a URL, an email, a phone number, Wi-Fi credentials, or a contact card. Download PNG or SVG. Nothing is uploaded. Generators Random String Generator New
Generate random strings, tokens, and keys with a custom alphabet and a live entropy estimate, all in your browser. Nothing is uploaded. Generators Reading Time Calculator New
Calculate the reading and speaking time of any text instantly in your browser. Text Utilities Remove Accents
Strip accents and diacritics, converting text to plain ASCII letters. Text Utilities Remove Blank Lines
Delete empty and whitespace-only lines from text instantly in your browser — no uploads required. Text Utilities Remove Duplicate Lines
Remove repeated lines from text, keeping the first occurrence. Text Utilities Remove Emoji New
Strip every emoji from text in one paste, leaving words, punctuation, and spacing intact. Runs in your browser. Text Utilities Remove Extra Spaces
Collapse multiple spaces and tabs into single spaces. Text Utilities Remove Line Breaks
Remove line breaks and join wrapped text into one paragraph. Text Utilities Remove Tabs
Replace tab characters with spaces instantly in your browser — paste, convert, and copy with no uploads. Text Utilities Reverse Text
Reverse text character by character, online and private. Text Utilities ROI Calculator New
Calculate return on investment from what you paid and what it is worth now, including the annualized return most ROI tools skip. Money & Finance ROT13 Encoder / Decoder New
Encode or decode ROT13 text instantly in your browser. ROT13 is its own inverse, so one pass does both directions. Developer Utilities Rule of 72 Calculator New
Estimate how long it takes for money to double at a given rate of return using the Rule of 72. Money & Finance Running Pace Calculator New
Turn a distance and a finish time into pace per kilometre and per mile, plus predicted 5K, 10K, half and full marathon times. Health & Fitness Savings Goal Calculator New
Work out how much to save each month to reach a savings goal by a target date, including expected investment returns. Money & Finance Scientific Calculator New
Free scientific calculator for students: order of operations, trig, logs, powers, roots, factorials, constants, memory, and history. Runs in your browser. Number Utilities Sentence Case Converter
Convert text to sentence case — capitalize the first letter of each sentence. Text Utilities Sentence Counter New
Count sentences in any text instantly. Works by detecting sentence-ending punctuation. Text Utilities SHA-1 Hash Generator New
Generate a SHA-1 hash from any text instantly in your browser. Fast, private, and free. Developer Utilities SHA-256 Hash Generator New
Generate a SHA-256 hash from any text instantly in your browser. Fast, private, and free. Developer Utilities SHA-512 Hash Generator New
Generate a SHA-512 hash from any text instantly in your browser. Fast, private, and free. Developer Utilities SIP Calculator New
Calculate the future value of a monthly SIP investment, the total you contribute, and the wealth your returns add over time. Money & Finance Slugify Text
Turn any text into a clean, lowercase, hyphenated URL slug. Text Utilities snake_case Converter
Convert text to snake_case for Python variables and database columns. Text Utilities Space Counter New
Count the number of space characters in your text. Shows spaces, total characters, characters without spaces, and word count. Runs in your browser. Text Utilities Tax Calculator
Add sales tax or VAT to a price, or work backwards from a tax-inclusive total, and see the tax amount. Number Utilities TDEE Calculator New
Estimate your Total Daily Energy Expenditure and the calories to eat to lose, maintain, or gain weight, using the Mifflin-St Jeor formula. Health & Fitness Text Compare New
Compare two texts side-by-side and see exactly what changed. Line-by-line diff with added, removed, and unchanged lines. Runs in your browser. Text Utilities Timezone Converter New
Convert a date and time from one timezone to another, with UTC time, each zone offset, and the exact hours difference. Daylight saving handled automatically. Date & Time Tip Calculator New
Calculate the tip and total bill, and split the cost between any number of people. Number Utilities Title Case Converter
Convert text to Title Case — capitalize the first letter of each word. Text Utilities Todo List New
Create tasks, organize subtasks, and track progress directly in your browser. Private, lightweight, and free. Productivity Trim Text
Trim leading and trailing whitespace from every line. Text Utilities Unix Timestamp Converter New
Convert a Unix timestamp to a human date, or a date back to a timestamp, in seconds or milliseconds, with the UTC time, ISO 8601 string, and your local time. Date & Time Uppercase Converter
Convert any text to UPPERCASE instantly in your browser — paste, convert, and copy with no uploads. Text Utilities URL Encoder & Decoder New
Percent-encode and decode URL components instantly in your browser. Fast, private, and free. Developer Utilities UUID Generator New
Generate random version 4 UUIDs in your browser. Make one or many at once, toggle hyphens and case, and copy them all. Nothing is uploaded. Generators Water Intake Tracker New
Tap to log glasses of water, hit your daily goal, and build a streak. A private hydration tracker with a weekly chart, right in your browser. Health & Fitness Word Counter New
Count words, characters, sentences, and paragraphs in any text. Text Utilities Word Frequency Counter New
Count how many times each word appears in your text, with percentages, sorting, and a common-word filter. Runs in your browser. Text Utilities YAML to JSON Converter New
Convert YAML to JSON for APIs, JSON Schema validation, and tools without a YAML parser. Handles anchors, multi-line strings, and timestamps. In-browser, free. Developer Utilities No matching tools found. Suggest it →