160 tools. Zero network requests.

Find a percentage of a number, what % one number is of another, and more.

Calculate a discounted sale price or a marked-up selling price instantly.

Calculate your exact age in years, months, and days.

Calculate the difference between two dates with a live countdown to future dates.

Count down to a named event, live to the second, in any time zone. Save several and share a full-screen link.

Every US federal holiday and observance for any year, with observed dates and calendar export.

A printable monthly and yearly calendar for any year, with holidays marked, ISO week numbers and your own events.

Convert times across time zones instantly. Multi-zone view with DST-aware offsets and a visual timeline.

Find sunrise, sunset, solar noon, and twilight times for any location and date.

Convert between cooking, length, weight, temperature, and volume units.

Plot your child's height, weight, and head circumference on WHO and CDC growth charts with percentile and adult height prediction.

Convert fractions to decimals and back, with millimetres alongside and the nearest 1/16, 1/32 or 1/64 mark.

Convert numbers to Roman numerals and back, with subtractive notation and input validation.

Simplify a width/height into a ratio like 16:9, or find a missing dimension from a ratio and one known side.

Convert shoe sizes between US, UK, EU, and Japan (JP), plus foot length in cm, for men, women, and kids.

Calculate running pace, time, or distance from the other two, with race presets and a splits table.

Calculate weighted GPA from courses by grade and credit hours, with +/- grades and a cumulative mode.

Find the best bedtime for a wake-up time, or wake-up times for a bedtime, based on 90-minute sleep cycles.

Calculate trip fuel cost from distance, efficiency, and price, or find your actual MPG or L/100km.

Four-function and scientific calculator with parentheses, exponents, and keyboard input.

Find what an appliance costs to run per day, month, and year from its wattage and your rate.

Estimate a due date from your last period, conception date, or a known due date, with weekly milestones.

Cubic yards and bag counts for a slab, footing, column, post hole, or flight of stairs.

Estimate gallons of paint for a room from its dimensions, doors, windows, and coats.

How many pieces fit in a sheet of plywood, fabric, or vinyl — with saw kerf, mixed rotation, and a cutting diagram.

Boxes of tile, plank, or laminate for any number of rooms — with areas left out and waste set by the lay pattern.

The AWG size a run actually needs — checked against NEC ampacity and voltage drop, with a full copper and aluminum reference table.

Gear inches, development, gain ratio, and speed or cadence for every gear on your bike.

Generate secure random numbers, flip coins, and roll dice.

Spin a wheel to pick from your own list, weight any entry, or draw several winners with or without repeats.

Generate strong random passwords and passphrases with entropy-based strength estimates.

Generate random usernames and display names from adjective-noun combinations.

Calculate sales tax and total price. Add tax to a price or extract it from a total.

Calculate tip amount, total bill, and per-person split instantly.

Split a bill between people with per-item custom shares and proportional tax/tip.

Convert pay between hourly, weekly, biweekly, monthly, and annual with overtime, estimate take-home, and compare offers.

Calculate monthly payments, total interest and a full amortization schedule — or compare two or three offers side by side and find the break-even.

Compare renting against buying over time — mortgage, taxes, maintenance, appreciation and the opportunity cost of your down payment.

See how your savings grow with compound interest and optional monthly contributions.

Project your retirement savings in today's dollars, and the monthly income they buy from the day you stop until the age you set.

Track income and expenses by category, set monthly budgets, manage savings goals, and view spending trends.

Log hours by project and task, view weekly and monthly summaries, and export for billing.

Keep a checklist of recurring bills that comes back every month — tick each one off as you pay it, and see what each has actually cost.

Your personal recipe manager. Save, organize, and search recipes, scale any one of them to the number of servings you need, and add its ingredients to your grocery list. Group them into boards like "Weeknight Dinners" or "Mom's Recipes."

Scale recipe ingredient quantities up or down. Handles fractions, mixed numbers, and ranges.

Plan your meals for the week, build a reusable recipe library, and generate a grocery shopping list.

Plan raised beds a square foot at a time — crop spacing, companion and sun warnings, soil for each bed, a planting calendar from your frost dates, crop rotation and a planting log.

Manage your standing grocery list, flag sale items and deals, track shopping trips, see an estimate of what you still have at home, and get smart restock suggestions. Send a recipe's ingredients straight to it from Recipe Box.

Work out how many pizzas to order for a group, with slices per person, leftovers and a topping split.

Your personal reading library. Keep the books you own and have read, track where you are in each, organize them into boards, rank them on tier lists, and publish a board to share by link. Works offline, and syncs through your own Google Drive.

Log your period and symptoms privately, and see your average cycle, next predicted period and estimated fertile window.

HIIT and Tabata timer: set work, rest and rounds, and follow the countdown with a beep at every change.

Focus in 25-minute blocks with short breaks and a long one every fourth session, all adjustable, with today’s focused time counted.

Calculate your Body Mass Index from height and weight. Metric and imperial.

Estimate calories burned during exercise by activity, duration, and body weight.

Log lifts set by set, see personal records by estimated one-rep max, and chart your progress per exercise — kg or lb.

Wilks, Wilks-2, DOTS and IPF GL points side by side from one total and bodyweight — with IPF GL for classic or equipped, three-lift or bench only.

Your estimated one-rep max by Epley and Brzycki side by side, with a percentage-of-1RM table and rep maxes from 1 to 12.

Stopwatch with lap tracking and countdown timer with audible alarm.

Log the water you drink in ml, fluid ounces or cups, against a daily goal, with the last seven days charted. Stored only in your browser.

Tick off daily habits, see the last seven days at a glance, and keep current and best streaks. Stored only in your browser.

Breathe along with a growing and shrinking circle — box breathing, 4-7-8 or your own timings, with a bell.

A private daily journal kept in your browser. One entry per day, full-text search, Markdown export, and optional sync to your own Google Drive.

Tagged, searchable bookmarks with notes — import and export bookmarks.html, synced through your own Google Drive if you like.

Private notes linked like a wiki — [[link]] one note to another, see what links back, tag with #words, search it all.

Flashcard decks with spaced repetition — FSRS schedules each card for just before you would forget it. CSV import, share a deck by link.

Build a family tree in your browser — a four-generation pedigree, partial dates, and GEDCOM import and export for genealogy software.

A private, offline-first task manager. Create tasks with due dates and priorities, organise into lists, and track subtasks.

Generate placeholder text by paragraphs, sentences, or words. Classic Latin, English-like, or Hipster Ipsum.

Count words, characters, sentences, paragraphs, and estimated reading time.

Measure your typing speed in WPM and your accuracy, see the keys you miss most, and keep a history on your device.

Compare two blocks of text and highlight every insertion, deletion and change — by line, word or character.

Write Markdown and see it rendered live, with tables, task lists and fenced code. Copy the HTML or export a standalone file.

Convert a DRM-free EPUB to Markdown or plain text, chapters in reading order, headings, lists and emphasis kept. Runs in your browser; the book is never uploaded.

Parse cron expressions into plain English, preview the next scheduled run times, and browse common patterns.

Calculate IPv4 subnet details from CIDR notation — network address, broadcast, host range, mask, and subnet splitting.

Decode, verify and sign JSON Web Tokens. Inspect header, payload and claims, check a signature with HS/RS/ES algorithms, or build and sign a new token.

Convert between CSV and JSON formats. Handles RFC 4180 quoting, custom delimiters, type inference, and table preview.

Convert a .vcf contacts file to CSV and back — every number, email and address kept, iPhone and Google exports both read. Runs in your browser; nothing is uploaded.

Convert an .ics calendar file to CSV and back — time zones, all-day events and repeat rules kept. Runs in your browser; nothing is uploaded.

Test and debug regular expressions with live match highlighting, capture group extraction, and flag toggles.

Generate SHA-256, SHA-384, and SHA-512 hashes, or an HMAC with a secret key, from text.

Create a .zip from your files, or open one, preview its text files and save what is inside. Nothing is uploaded.

Compress or decompress text and files as gzip, zlib or raw deflate, and see the size before and after. Nothing is uploaded.

Compute a file’s SHA-256, SHA-384, SHA-512, SHA-1 or MD5 checksum and compare it against a published value. Nothing is uploaded.

Convert numbers between binary, octal, decimal, and hexadecimal.

Convert between Unix timestamps and human-readable dates. Live clock included.

Generate v4 (random), v5 (deterministic), and v7 (time-ordered) UUIDs.

Format and prettify JSON, or minify it for production. Validates JSON instantly.

Generate TypeScript interfaces or type aliases from pasted JSON. Merges mixed arrays, quotes awkward keys, and resolves name collisions.

Convert text between camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE, Title Case, and more.

Describe a system in a few lines — components, what talks to what, and what sits inside a boundary — and get a laid-out architecture diagram. Share it as a link, export SVG or PNG.

Draw a flowchart — steps, decisions and labelled arrows, placed by hand. Export SVG or PNG, or share the whole chart as a link.

Encode text to Base64 or decode Base64 back to plain text.

Encode text for URLs or decode percent-encoded strings back to plain text.

Encode and decode ROT13, Caesar, Atbash, Vigenère and XOR ciphers, with a brute-force view for all 25 Caesar shifts.

Generate QR codes for URLs, text, Wi-Fi, contacts, email, and SMS. Customize colors and download as SVG or PNG.

Scan a QR code with your camera or from a screenshot. Reads links, Wi-Fi passwords, contacts, email, SMS and map locations — nothing leaves your device.

Encode special characters to HTML entities and decode entities back to plain text. Supports named, decimal, and hexadecimal formats.

Cut the background out of any photo, then keep it transparent or fill it with a colour, an image or a blur. Runs on your device — no uploads, no sign-up, no watermark.

Crop, rotate, resize, and compress images to AVIF, WebP, JPEG, or PNG. Fully client-side — your image never leaves the browser.

See the GPS location, camera and other metadata in a photo, then remove it without re-compressing the picture. JPEG, PNG and WebP.

Vectorize PNG, JPG, WebP, or GIF images into clean, scalable SVG. Trace logos, icons, and line art fully in your browser.

Generate harmonious color palettes from any base color — typed, randomized, or picked off your screen in Chrome and Edge. Complementary, analogous, triadic, tetradic, and more.

Preview colors, palettes and images with protanopia, deuteranopia, tritanopia or achromatopsia, and find pairs that stop being distinguishable.

Convert colors between hex, RGB, HSL, HSV and OKLCH, or pick one off your screen in Chrome and Edge. Gamut indicator, Display P3 output, tonal scales, harmonies, and a WCAG contrast checker.

A simple online paint program: pencil, eraser, fill, lines, rectangles and ellipses, with undo and PNG download. Works offline, nothing is uploaded.

An on-screen ruler in centimetres, inches and pixels. Calibrate it once against a bank card and the millimetres are real ones.

Backing, batting, binding, borders, sashing and cut sizes for quilt shapes, plus yardage converted between fabric widths — in inches and yards.

Spread increases or decreases evenly across a knitting or crochet row, written out as an instruction with both stitch counts checked.

How much yarn a knitting or crochet project needs, from your own gauge — plus skeins to buy, yarn substitution and foundation chains.

Use your phone as a digital bubble level. Check if any surface is level or plumb using your device's accelerometer.

Live GPS coordinates, altitude, speed, and compass heading from your device.

Upcoming solar and lunar eclipses from your location: local times, how much of the sun is covered, and whether you are in the path of totality.

Moonrise, moonset, transit, phase, illumination and moon age for any location and date.

Tide times and heights for US coastal stations, with the full tide curve and the year's biggest tides.

Find Hohmann transfer windows between any two solar system bodies, with countdown, timetables, and ΔV estimates.

Put top and bottom text or a caption on your own picture, and download it — no watermark, no upload.

Pokémon type matchups: every weakness and resistance of one or two types, or the full 18-type chart.

Discover your natal chart: sun sign, moon sign, rising sign, and planet placements.

Find out how old your dog is in human years, accounting for size and breed.

Find out how old your cat is in human years using AAHA guidelines.

Printable 5x5 bingo cards — classic B-I-N-G-O numbers or your own words and phrases. Up to 24 per batch, PNG download, print view, shareable link.

Slide and merge numbered tiles on a 4x4 grid with the arrow keys or a swipe. Best score saved locally.

Endless downhill skiing. Dodge trees and rocks, hit ramps for air, and share the seed so someone else can ski the same slope.

Falling-notes piano game. Play fourteen public-domain tunes — short or full-length — on a real keyboard or five arcade lanes, by touch, mouse or typing.

Steady click from 20 to 300 BPM, with tap tempo, eight time signatures, an accented downbeat and subdivisions. Shareable as a link.

Play a note and see which one it is and how many cents sharp or flat, with presets for guitar, bass, ukulele and violin and an adjustable reference pitch.

Play a steady sine, square, triangle or sawtooth from 20 Hz to 20 kHz, with a note picker and a left/right channel test. For tuning by ear and testing speakers.

Print blank staff paper: treble, bass or grand staff, optional guitar tab, on US Letter or A4 at the staff size you write at.

White, pink and brown noise plus synthesised rain, made in your browser with a sleep timer. No audio files and no loop you can hear.

Endless lo-fi beats composed live in your browser — piano, swung drums, bass — with rain, fire, waves and birdsong to mix in. Share a track by link.

Classic Snake on a 20x20 grid. Steer with the arrow keys or a swipe, eat apples to grow, and go faster with every three you catch.

Noughts and crosses for two players on one device, or against a computer at three levels — including perfect play, which can be drawn but never beaten.

Drop discs and line up four on a 7x6 grid — a Connect Four-style game for two players on one device, or against a computer at three levels.

Run Conway’s Game of Life in your browser. Draw cells, load gliders, pulsars and the Gosper glider gun, paste any RLE pattern, and share a board by link.

A pipe-laying puzzle game. Build a pipeline ahead of the flowing water, score by distance, and race the clock. Seeded boards, no ads or tracking.

A tower defense game. Build a maze of towers, reroute the creeps walking to your goal, and survive as many waves as you can. Seeded maps, no ads or tracking.

A falling sand game in your browser. Pour sand, water, oil and acid, grow plants, set fire to them, and share the box you built by link.

A toy train set in your browser. Lay track, points and signals, couple up cars, and run trains — too fast into anything and they derail. Share a layout by link.

Play checkers — English draughts — for two players on one device, or against a computer at three levels. Compulsory captures, kings, and a running scoreboard.

Play mancala with Kalah rules — sow seeds, land in your store to go again, capture from the pit opposite. Two players on one device, or against a computer at three levels.

Play Klondike solitaire — draw 1 or draw 3, unlimited undo, and numbered deals you can replay. Your game is saved as you play.

Play Minesweeper with Beginner, Intermediate and Expert boards, or set your own grid size and mine count.

Flip two cards at a time and find every matching pair. 4×4 or 6×6, with moves, a timer and your best score.

Play or print a word search from a theme or your own words, in easy, medium or hard, and share the exact puzzle by link.

Play Sudoku with four difficulty levels, pencil marks, undo, conflict highlighting and a daily puzzle. Your game is saved as you play.

Create drag-and-drop tier list rankings. Add items as text or images, customize tiers, and export as PNG or shareable file.

Color-mixing painting game: mix realistic paints to match a target palette, then brush-paint a coloring page. Works offline.

Join every pair of dots so that every square on the board is used — the Flow Free puzzle, at four sizes, with a daily board. Works offline.

Kids’ dinosaur game: brush away the dirt to find the bones, build the skeleton, paint it, then play fetch, feed it and teach it to dance.

Drop numbered discs into a 7×7 grid — a disc clears when its number matches its row or column count, and clears set off chains. Works offline.

Drag through neighbouring dots of one colour to clear them — close a loop and every dot of that colour goes. 60-second and 30-move modes. Works offline.

A Flappy-Bird-style one-tap game: tap to rise, gravity does the rest, fly through the gaps. Works offline.

A rotating-tunnel reflex game: hold left or right to circle a hexagon and slip through the gaps in the closing walls. Works offline.

A Plinko-style peg-drop game with no stakes: aim five balls through the pegs for points, or fill a Galton board and watch the bell curve form. Works offline.

Fill a spare screen with a starfield, Mystify, Bézier curves, a Lissajous scope, a Chladni plate, bouncing text, glyph rain or a drifting clock. Works offline.

Turn a phone, tablet or TV into a sign: your message fills the whole screen, with slides and a countdown if you want them, and the link opens straight into it. Works offline.

A Simon-style pattern memory game: watch the four pads light up, tap them back, and beat a clock that keeps shortening. Colour, shape and note all carry the pattern. Works offline.

A party's Low, Moderate and High XP budgets for a fifth-edition combat encounter under the 2024 rules, and which difficulty your monsters add up to.