All tools

Collections

Weight conversions (kg → pounds) Any weight in pounds, stones and ounces, plus the healthy height range. Roman numerals by year How to write any year (1900–2100) in Roman numerals, with its breakdown. Hourly wage → yearly salary See how much any hourly rate is per year, month, biweekly and week. Timers with alarm Ready countdowns from 1 to 90 minutes, with a sound alarm and full screen.

Finance

Converters

Tile calculator Work out how many tiles, square meters and boxes you need for your floor or wall, with waste allowance and common sizes from 30x30 to 60x60 cm. Concrete calculator (cement, sand, gravel) Estimate cement bags, sand, gravel and water for slabs and floors: enter dimensions or m³, pick a 1:2:3, 1:2:4 or 1:3:5 mix, bag size and waste factor. Paint calculator (how much do I need) Work out how much paint you need: wall area minus doors and windows, coats and coverage rate, with instant results in liters and gallons. Free. Percentage calculator Find X% of any number, see what percent one value is of another and get the percentage change between two amounts in real time. Free, no sign-up. Celsius to Fahrenheit converter Convert Celsius to Fahrenheit (and °F to °C) instantly, with the exact formula, a temperature table and fever and oven examples. Free, no sign-up. CM to inches converter Convert centimeters to inches (and inches to cm) instantly, with the exact formula, a conversion table and feet-and-inches output. Free, no sign-up. Data storage converter (MB, GB, TB) Convert bit, Byte, KB, MB, GB, TB and PB instantly. Switch between decimal (1000, SI) and binary (1024, IEC) and see why your 1 TB drive shows only 931 GB. Angle converter Convert angles between degrees, radians, gradians, turns, arcminutes and arcseconds. Type one value and see every equivalent instantly, free and offline. Area converter Convert area between m², ft², km², hectares, acres, square yards and the Dominican tarea. One value shows every other unit instantly. Free, no sign-up. Cooking measurement converter Convert ml, liters, cups, tablespoons, teaspoons, ounces, pints and quarts, plus approximate grams per ingredient. Free tool, no sign-up needed. Fuel economy converter Convert fuel economy between L/100km, km/L, US MPG and UK MPG instantly. Enter one value and see every other unit at once, with a reference table. Currency converter Convert dollars, euros, Dominican peso and more using ECB reference rates via Frankfurter. Shows the live rate and its date. Free and no sign-up. Energy converter Convert energy between joule, kilojoule, calorie, kilocalorie, watt-hour, kWh, BTU and electronvolt instantly. Type one value and see every equivalent at once. Power converter Convert power between watts, kilowatts, mechanical horsepower, metric CV and BTU/h instantly. Type one value and unit to see every other. Free tool. Pressure converter Convert pressure between pascal, kPa, bar, psi, atmospheres, mmHg and mbar. One value shows every other unit at once. Free, client-side, no sign-up. Clothing & shoe size converter Convert clothing and shoe sizes between US, EU, UK, Mexico and Spain: women, men and kids, including S/M/L sizing and foot length in cm. Free. Time unit converter Convert seconds, minutes, hours, days, weeks, months and years instantly. Type one value and see every time equivalent, with average-length months and years. Speed converter Convert speed between m/s, km/h, mph, knots and feet per second instantly. Type one value and unit to see every other unit. Free, no sign-up needed. Grams to ounces converter Convert grams to ounces (and ounces to grams) instantly, with the formula, a handy conversion table and the troy ounce for gold. Great for cooking. Free. KG to lbs converter Convert kilograms to pounds (and pounds to kg) instantly with the exact factor, a handy conversion table and stones output. Free, no sign-up. km/h to mph converter Convert km/h to mph and mph to km/h instantly. For car speedometers, GPS and US speed limits. 1 mph = 1.609344 km/h, with a ready-to-use table. Liters to gallons converter Convert liters to gallons and gallons to liters instantly, with a US and imperial (UK) gallon selector, the exact formula and a handy conversion table. Meters to feet converter Convert meters to feet and feet to meters instantly, with the result also shown in feet and inches. Great for height, construction and altitude. Miles to KM converter Convert miles to kilometers and km to miles instantly with the exact 1.609344 factor, race distance table and mph to km/h guide. Free, no sign-up. Roman numerals converter Convert Roman numerals to numbers and numbers to Roman (1 to 3999) instantly, with error validation, the rules explained and a symbol reference table. Feet and inches to cm (height) Convert your height from feet and inches to centimeters and meters, and from cm back to feet and inches (5'10"). Exact factors, height chart and formula. Rule of three calculator Solve direct and inverse rule of three problems instantly: enter three values and get the unknown X, with the formula and worked examples. Free, no sign-up. Cups to ml converter (cooking) Convert cups, milliliters, tablespoons, teaspoons and fluid ounces instantly. Perfect for cooking US recipes with the right measures. Free, no sign-up.

Text, PDF & Image

Find and replace text Find and replace text in large blocks: match case, whole word, and full regular expression mode with capture groups. Counts every match and copies the result. Image compressor Compress JPG, PNG and WebP images in your browser: adjust quality, see the savings instantly and download files one by one or as a ZIP. Nothing is uploaded. Character counter Live character count with limit bars for X/Twitter, Instagram, SMS, meta descriptions and SEO titles, so you always know how many characters remain. Word and character counter Count words, characters, sentences and paragraphs live as you type, with estimated reading time. Your text never leaves your browser. Word frequency counter Count how many times each word appears in a text and rank them by frequency with counts and percentages. Optional stopword filter. Runs in your browser. Case converter Convert text to UPPERCASE, lowercase, Title Case, Sentence case, alternating or inverted case in real time. One-click copy, free, private and no sign-up. Split PDF Split a PDF right in your browser: extract a page range or separate every page into its own file inside a ZIP. Free, private, nothing gets uploaded. Remove duplicate lines Remove duplicate lines from any list of text right in your browser: ignore case or spaces, drop blank lines, and keep the order or sort it A to Z. Extract emails and URLs from text Extract every email address and URL from any pasted text: pick what to find, remove duplicates, sort them and choose the separator, then copy in one click. Favicon generator Create your website favicon free: type a letter or emoji, or upload an image, then download the PNG pack (16 to 512) plus a favicon.ico. All in your browser. Lorem Ipsum generator Generate Lorem Ipsum filler text in your browser: choose paragraphs, sentences or words (1-50), with or without the classic opening, and copy it in one click. Image to Base64 converter Convert a PNG, JPG, GIF, WebP or SVG image to a Base64 data URI inside your browser. Copy the data URI, the <img> snippet or the CSS background in one click. Reverse text Reverse text instantly: flip all characters, reverse word order, reverse line order or mirror each line. Copy the result with one click, free. JPG to PDF converter Merge several JPG, PNG or WebP images into one PDF right in your browser: reorder pages, pick the page size and download. Free — nothing gets uploaded. MP4 to MP3 converter Pull the audio out of your own MP4, M4A or WebM videos and save it as MP3 (128/192/320 kbps). It all runs in your browser — your file is never uploaded. Sort and dedupe lines Sort lines of text alphabetically A to Z or reversed, remove duplicate and empty lines, trim extra spaces, and shuffle at random in your browser. Paraphrasing tool (on-device AI) Paraphrase and rewrite text with AI that runs IN your browser (Gemini Nano): your text never leaves your device. Formal, simple and creative styles. PDF to JPG converter Convert every page of a PDF into JPG images right in your browser: pick the quality and download one photo or a ZIP. Free, files never leave your device. Remove accents Remove accents and diacritics from any text instantly: convert ñ to n, strip punctuation and lowercase, then copy. Free, private, no sign-up. Remove extra spaces Clean extra spaces, tabs and blank lines from your text: collapse double spaces, trim each line and merge paragraphs. Free and fully in your browser. Crop image Crop JPG, PNG or WebP images in your browser: adjustable crop box, presets for 1:1, 4:3, 16:9 and 9:16, and lossless download. Nothing is uploaded. Image resizer Resize images to exact pixel dimensions right in your browser: social media presets, aspect-ratio lock and instant download. Free, private, no sign-up. Rotate & flip image Rotate an image 90° left or right, 180°, or mirror it horizontally or vertically, all in your browser with no quality loss. Download in the same format. Spanish syllable separator Split Spanish words into syllables with RAE rules — diphthongs, hiatuses, consonant clusters — and see the stressed syllable and stress type of each word. Text to speech Turn any text into speech right in your browser: pick a voice, adjust speed and pitch, then listen out loud. 100% local, nothing is ever uploaded. Merge PDF Combine multiple PDFs into a single file right in your browser: drag, reorder and download. Your documents are never uploaded to any server. WebP to JPG converter Convert WebP images to JPG for free without uploading anything: drop your files, they convert inside your browser and download one by one or as a ZIP.

Programming

Base64 encode / decode Encode and decode Base64 with full UTF-8 support — accents and emojis handled correctly. Paste text, copy the result instantly. Free, no sign-up. Diff checker — compare text Compare two texts line by line: additions in green, deletions in red, plus change counters. Runs 100% in your browser, so private text never leaves your device. AI token counter (GPT) Count the tokens in your text for GPT models (o200k and cl100k), plus characters, words and an editable cost estimate. Everything runs in your browser. Color contrast checker (WCAG) Check the color contrast between text and background to WCAG: exact ratio and whether it passes AA and AAA for normal and large text. Free, no sign-up. HEX / RGB / HSL color converter Convert a color between HEX, RGB and HSL in any direction: type any of the three formats and get the other two with a live swatch and one-click copy buttons. Unix timestamp converter Convert Unix timestamps to readable dates in local time and UTC, or any date to seconds and milliseconds. Auto-detects the unit, right in your browser. Crontab expression explainer Translate any 5-field cron (crontab) expression into plain English and preview the next run times. Supports asterisk, */n, lists and ranges. HTML entities encoder / decoder Encode and decode HTML entities: turn < > & quotes and apostrophe into < & and back to plain text. Runs in your browser, free, no sign-up needed. HTML formatter (beautify) Free HTML formatter in your browser: beautify and indent minified or one-line HTML with two spaces so it is readable again, then copy it in a click. JSON formatter & validator Format, validate and minify JSON right in your browser: 2 or 4 space indentation and syntax errors with exact line and column. Free, no sign-up. SQL formatter Free SQL formatter that runs in your browser: uppercase keywords, line breaks before every clause and clean indentation for SELECT, JOIN, WHERE and ORDER BY. XML formatter Format and indent XML right in your browser: turn a messy one-line file into readable code with 2 or 4 spaces, plus minify and copy. Free, no sign-up needed. CSS border-radius generator Generate CSS border-radius with sliders for all 4 corners or an 8-value blob mode. Live preview, a random blob button and one-click copy. Free tool. CSS box-shadow generator Build CSS shadows with sliders for X, Y, blur, spread, color with opacity and inset. Stack several layers, preview live and copy the box-shadow code. Password generator Generate strong random passwords in your browser with cryptographic randomness: length slider, symbols and an entropy strength meter. Free, no sign-up. Meta tags generator (SEO and Open Graph) Generate SEO, Open Graph and Twitter Card meta tags from a simple form. Length counters, safe escaping and one-click copy. No sign-up, runs in your browser. CSS gradient generator Build linear, radial and conic CSS gradients with a live preview, up to 6 color stops, angle control and ready-to-copy code. Free, no sign-up. Hash generator (MD5, SHA-256) Generate MD5, SHA-1, SHA-256 and SHA-512 hashes from any text instantly in your browser, with one-click copy for every result. Free and no sign-up needed. Random number generator Generate unbiased random numbers in your browser with cryptographic randomness: pick a range, how many, and a no-repeats option for raffles and draws. QR code generator Create QR codes for URLs, WiFi or text with custom colors, size and error correction. Generated in your browser and downloadable as PNG or SVG. Robots.txt generator Build a valid robots.txt in seconds: allow or block bots, Allow and Disallow rules, crawl-delay and sitemap. Ready presets, live preview and copy. Slug generator Turn any text into a clean URL slug: lowercase, no accents, spaces and symbols become hyphens. Live preview and one-click copy. Free, no sign-up. UUID generator Generate up to 100 random UUID v4 identifiers in your browser, in lowercase or uppercase, and copy one or all with a single click. Free, no sign-up. JSON to CSV converter Convert a JSON array to a CSV table for Excel and back to JSON for your APIs. Pick the delimiter, escape commas and quotes, then copy or download it. JWT decoder Decode any JWT right in your browser: view the header and payload as JSON, with human-readable exp and iat dates plus an expiry check. No sign-up. Markdown to HTML converter Convert Markdown to HTML in your browser: headings, bold, lists, links and code blocks, with a live preview. Free, safe and no sign-up needed. CSS minifier Minify CSS in your browser: strip comments, spaces and line breaks, collapse to one line and see how many bytes and what percentage you save. Free, no sign-up. HTML minifier Minify HTML in your browser: strip comments and whitespace between tags without breaking pre, textarea, script or style. See the bytes and percentage you save. Regex tester Test regular expressions live: highlighted matches, capture groups and JavaScript flags. Runs fully in your browser, free, private and with no sign-up. Color picker (HEX, RGB, HSL) Convert colors between HEX, RGB and HSL in real time, with a tint and shade palette, complementary color and one-click copy for every value. Free, no sign-up. Text to binary (and binary to text) Convert text to binary and binary back to text with correct UTF-8 for accents and emojis. Shows decimal and hex for each character. Free, no sign-up needed. URL encoder / decoder Encode and decode URLs (percent-encoding): turn spaces and accents into %20, %C3%A9 and back again. Copy the result instantly. Free, no sign-up.

Dates & Time

Age calculator Work out exact age in years, months and days from a date of birth, plus total weeks, total days and the countdown to the next birthday. Free, no sign-up. Hours calculator Count hours and minutes between a start and an end time, subtract lunch breaks and get payroll-ready decimal hours. Overnight shifts handled automatically. Time zone converter Convert a time from one time zone to another with daylight saving (DST) handled automatically. Compare cities, see the offset and never miss a call. Online stopwatch and timer Online stopwatch with laps down to hundredths of a second, plus a countdown timer with a sound alarm. Accurate, free and nothing to install at all. Countdown timer Live countdown to any date: watch the days, hours, minutes and seconds left until your event. One-click Christmas and New Year presets. Free. What day of the week Find out what day of the week any date falls on, past or future. Shows the weekday, the day number within the year and whether the year is a leap year. Days between dates Count the exact days between two dates, with weeks, months, years and Monday-to-Friday business days. Perfect for deadlines. Free, no sign-up. Business days calculator Count the business or working days (Monday to Friday) between two dates, skipping weekends and any holidays you paste in. Free and no sign-up needed. Days alive calculator Find out how many days you have been alive since birth: days, weeks, months, hours and minutes, your birth weekday and your next round-day milestone. Week number (ISO 8601) Find out which ISO 8601 week number (1-53) a date falls in, with the ISO year and its Monday-to-Sunday range. Free, instant and no sign-up. Weeks between two dates Work out how many weeks are between two dates: total days, full weeks plus leftover days, and weeks as a decimal. Free, instant, no sign-up needed. Add or subtract days from a date Add or subtract days, weeks, months or years from any date and get the exact result with its weekday. Perfect for deadlines and due dates. Free.

Health

Daily water intake calculator Find out how much water to drink daily from your weight, activity level and climate. Get the amount in liters and 250 ml glasses. Free, instant. Macro calculator Macro calculator: split your daily calories into grams of protein, carbs and fat by goal (balanced, keto, low-carb, high-protein). Free and private. Sleep calculator (cycles) Find the best time to go to bed or wake up based on 90-minute sleep cycles, so you wake up between cycles feeling rested, not groggy. Free tool. Pregnancy calculator Estimate your due date with the Naegele rule, plus current weeks and days of pregnancy, your trimester and how many days are left. Free and private. BMI calculator Work out your BMI from weight and height (kg/cm or lb/ft), see your WHO category and the healthy weight range for your height. Free, no sign-up. TDEE calculator Estimate your TDEE and basal metabolic rate with the Mifflin-St Jeor formula, plus daily calories to maintain, lose or gain weight. Free tool. Calories burned calculator Calculate calories burned by activity with the MET formula: your weight, exercise and minutes. Running, walking, cycling, swimming and more. Free. Blood glucose converter (mg/dL and mmol/L) Convert blood glucose between mg/dL and mmol/L both ways, with a fasting reference table for normal, prediabetes and diabetes ranges. Free and instant. Ovulation and fertile days calculator Estimate your fertile days, ovulation date and next period with the calendar method, using your last period and cycle length. Free, private and instant. Body fat calculator Estimate your body fat percentage with the US Navy method: sex, height, neck and waist (plus hip). Get your category by sex instantly. Free. Ideal weight calculator Find your ideal weight range from your sex and height: the healthy BMI range plus the Devine, Robinson and Miller reference formulas. No sign-up. Daily protein intake calculator Work out how many grams of protein you need per day from your body weight and goal: sedentary, active, fat loss or muscle gain. Free, instant, private. Heart rate zones calculator Find your maximum heart rate with 220 − age and the Tanaka formula, plus your 5 training zones in beats per minute, using the Karvonen method with resting HR. Running pace calculator Work out your running pace in min/km and min/mile, plus time and speed, from any two of distance, time and pace. Includes 5K, 10K, half and marathon splits. Body surface area (BSA) calculator Work out your body surface area (BSA) in m² with the Mosteller formula from height and weight, and compare it against Du Bois. Free, in your browser. One-rep max (1RM) calculator Estimate your one-rep max (1RM) with the Epley and Brzycki formulas from the weight lifted and reps. Includes a training load percentage table.

Education

Area and perimeter calculator Compute the area and perimeter of squares, rectangles, circles, triangles and trapezoids: enter the dimensions and get exact results instantly, free. Fraction calculator (with steps) Add, subtract, multiply, and divide fractions with steps: LCM of denominators, GCD simplification, mixed numbers, negatives, and the exact decimal. Logarithm calculator Compute the base-10 logarithm, the natural log (ln) and the logarithm in any custom base of a number instantly, shown with 6 significant figures. Final grade calculator Find out exactly what score you need on your final exam to pass or hit your goal grade: enter your current grade and the exam weight. Free and instant. Ratio and proportion calculator Solve proportions A:B = C:D for the missing term by cross multiplication and reduce ratios to lowest terms with the GCD, plus their decimal value. Combinations and permutations calculator Compute combinations C(n,r), permutations P(n,r) and the factorial n! with exact BigInt precision. Learn when order matters. Free, no sign-up. Number base converter Number base converter: change integers between binary, octal, decimal, hexadecimal and any base from 2 to 36 instantly. Free, client-side, no sign-up. Standard deviation calculator Get population and sample standard deviation with every step shown: mean, deviation table, sum of squares, variance and coefficient of variation. Quadratic equation solver Solve quadratic equations ax²+bx+c=0 with the general formula: real or complex roots, plus the discriminant and vertex computed instantly. Free, no sign-up. Prime factorization calculator Break a positive integer (2 to 10^12) into its prime factors with exponents, e.g. 360 = 2^3 x 3^2 x 5, and find out if it is prime. Free, in your browser. Fraction to decimal (and back) Convert a fraction to a decimal and a decimal back to a fraction: spot repeating decimals like 1/3 = 0.(3) and simplify with the GCD. Free, no sign-up. GCF and LCM calculator Find the GCF (greatest common factor) and LCM (least common multiple) of two or more numbers using the Euclidean algorithm, shown step by step. Free. Mean, median and mode calculator Paste your numbers and get the mean, median, mode, range, sum, count and standard deviation (population and sample) at once. Free, no sign-up. What do I need on the final exam Find the score you need on your final exam to pass: enter your current average and the exam weight. Includes scales for Mexico, Chile, Peru and Spain. Scientific notation converter Convert between decimal, scientific, engineering and E notation. Type 0.00042 or 4.2e-4 and get every equivalent form instantly. Free, no sign-up. Weighted average calculator Compute your weighted average using weights or credits: add grade-and-weight rows and see the result and total weight update live. Free, no sign-up. System of equations solver (2x2) Solve a 2x2 linear system with Cramer’s rule: enter a1, b1, c1, a2, b2, c2 and get x, y, the determinant and the full step-by-step. Free, no sign-up. Pythagorean theorem calculator Solve the Pythagorean theorem a²+b²=c²: enter two sides to get the third, plus the right triangle area and perimeter. Free, instant, no sign-up.

Random & Fun

Magic 8-ball Online Magic 8-ball: type your yes-or-no question and get one of the 20 classic answers, picked with cryptographic randomness. Free, no sign-up needed. Coin flip Flip a virtual coin online: tap and watch it spin in 3D to land on heads or tails with cryptographic randomness. Toss several at once and track totals. Random team generator Split a list of names into fair, balanced random teams using cryptographic shuffling. Choose by number of teams or by team size. Free, no sign-up. Username generator Generate original random usernames with gamer, aesthetic, numbers or underscore styles. Ten fresh ideas per batch with one-click copy. Free, no sign-up. Lottery number generator Generate random lottery combinations: pick how many numbers, the range and whether repeats are allowed. Cryptographic randomness, up to 10 lines. Dice roller Free online dice roller: D4, D6, D8, D10, D12, D20 and D100, from 1 to 20 dice with cryptographic randomness. See each die, the total sum and history. Rock paper scissors Play rock paper scissors against the computer with cryptographic randomness: pick your move, see who wins and keep a running scoreboard for the session. Spinner wheel (random picker) Free spinner wheel: type your options, spin the wheel and let a cryptographic random pick a winner. Share your wheel with a link. No sign-up needed. Random name picker Pick one or several random winners from your list of names. Fair unbiased draw powered by crypto, with a no-repeats option for raffles. Free, no sign-up. Yes or No (random decision) Random Yes or No decision maker: tap one button and a cryptographic coin flip picks for you, with an optional Maybe and a results counter. Free, no sign-up. Typing speed test (WPM) Measure your typing speed in words per minute (WPM) and your accuracy. Copy a sample text, see mistakes highlighted live and time yourself instantly. Click speed test (CPS) Measure your clicks per second (CPS) online for free. Pick 1, 5, 10, 30 or 60 seconds, click nonstop and see your speed and best score of the session.

Social Media

Engagement rate calculator Calculate the engagement rate of your account or post by followers or by reach, with the percentage and a rating from low to excellent. Invisible character (blank space) Copy an invisible character or blank space for empty usernames, bios and blank WhatsApp messages. Pick the symbol and how many times to repeat it. Social media character counter Character counter with the real limits of X, Instagram, TikTok, LinkedIn, YouTube, Facebook, Bluesky and Threads. See how many you have left per network. Thread splitter for X (Twitter) Split long text into 280 or 500-character tweets without cutting words, with automatic 1/n numbering and a copy button for every tweet. Free, no sign-up needed. Instagram fonts generator Turn your text into fancy fonts for Instagram, TikTok and bios: bold, italic, cursive, bubbles, upside-down letters and more. Copy and paste in a click. Text repeater Repeat any text as many times as you want (1-1000) with an optional separator and numbering. Copy the result and count its characters. Great for lists. Instagram line break generator Fix the line breaks in your Instagram bio and captions: keep blank lines and spacing with an invisible character. Copy and paste in one click.