Everyday tools.

Press every key, see it light up, and find keys that do not register.

See your camera's live picture, real resolution, and frame rate, and take a test photo.

Watch your microphone's level and waveform, then record a short clip and play it back.

Check your camera and microphone together, see the live picture and sound level, and record a five-second video call test.

Check a display for dead pixels, backlight bleed, banding, scaling blur, and refresh rate.

Test multi-touch, drawing, dead zones, and vibration on a phone or tablet.

Pixel density, dot pitch, and physical size from resolution and diagonal.

Compare two screens at the same physical scale, with width, height and area in inches and centimetres.

Compare a quiet sine tone or narrow-band noise from 250 Hz to 16 kHz, with fine tuning and hearing-safety guidance.

Test your typing speed in words per minute and your accuracy, over 15 seconds to 2 minutes, with common words in seven languages.

Count your clicks per second over 1 to 60 seconds, with your best score kept in your browser.

Click when the box turns green: your average reaction time over five rounds, in milliseconds.

See your public IP address, whether it is IPv4 or IPv6, and the approximate location, network, and time zone that websites see for your connection.

Screen resolution, pixel ratio, viewport, browser, system, graphics, and supported media formats, as a copyable report.

Estimated noise level in dB(A) from your microphone, with Leq, maximum, a chart, and calibration. For comparison, not certified measurement.

The camera light where the browser allows it, or a bright, warm, or red screen light, with an SOS signal.

Check left and right channels, centre image, bass, and speaker phase for headphones and speakers.

Find the highest and lowest tones you can hear on your headphones, step by step. Not a medical test.

Test every button, trigger, and stick of a game controller, see stick drift with a dead zone, and try vibration.

Test every mouse button and the scroll wheel, catch double-click faults, and estimate the polling rate.

Estimate mouse event rate with current, average and maximum Hz, a histogram and coalesced-event counts.

Check each mouse button for very short press intervals, with an adjustable threshold and timestamp log.

Find your screen's real refresh rate in hertz and watch a moving shape for blur and ghosting.

Click targets as fast and accurately as you can, with target size and time options, and beat your best score.

Keep the same mouse travel per turn when changing games or DPI, using documented console yaw or your own value.

See what any website can read about your browser without asking, and whether it adds up to a fingerprint that tracks you.

Take a webcam photo in the browser with a chosen look, soft skin, and square, portrait, or passport crops.

Use your camera as a mirror, with brightness, zoom, a light ring, and full screen.

Scan QR codes live with the camera and copy or open what they contain.

Use your phone's camera as a magnifying glass, with zoom, freeze, high-contrast views, and the torch.

A spirit level on your phone: bubble and angle, flat or on its edge, with calibration and hold.

Your phone's heading to magnetic north, or true north from your location with the World Magnetic Model.

Speed from GPS in km/h, mph, or knots, with maximum, average, distance, and the screen kept on.

Read a live or manual bearing on a 24 Mountains dial, with trigram rings and sitting and facing directions.

Place a compass-direction Bagua overlay on a local floor-plan image, adjust its orientation and export a PNG.

Create a high-resolution downloadable QR code from text or a URL.

wa.me links with a pre-filled message, a QR code, and a website button; Telegram t.me links too.

Make a QR code that joins your Wi-Fi when scanned, with the special characters escaped, as an image or a card to print.

Make a vCard QR code that saves your name, phone, email, company, and address to a phone's contacts when scanned.

Decode a QR code from a local image without an upload.

EAN-13, UPC-A, EAN-8, ITF-14, Code 128, and Code 39 barcodes in bulk, as SVG or PNG.

Create strong passwords locally with cryptographic randomness.

Check how guessable a password is with zxcvbn, with crack-time estimates and advice, entirely on your device.

Calculate percentages, ratios, and percentage change.

A big-button counter with several counters, goals, and keyboard shortcuts, saved in your browser.

Reduce image dimensions to a ratio and scale them proportionally.

A centimetre and inch ruler on your screen, calibrated to actual size with a bank card.

Measure an on-screen angle with two draggable arms and an optional local image, in 180° or 360° mode.

Convert decimal and binary file-size units accurately.

Near and far focus limits, total depth of field, and hyperfocal distance for any lens and sensor.

Engine power from torque and rpm, or torque from power, in kW, hp, and PS with N·m or lb·ft.

A simple calculator with very large buttons and numbers, a high-contrast mode, keyboard support, and spoken results.

How hot it feels from temperature and humidity, with the National Weather Service formula and danger levels.

How cold it feels from temperature and wind speed, with the frostbite risk.

Dew point from temperature and humidity, or humidity from the dew point, with how muggy it feels.

The temperature water boils at for any altitude or air pressure.

Density altitude from field elevation, altimeter setting, temperature, and dew point.

Wind speed to Beaufort force, with descriptions and the full table.

Get a reminder when your room is getting too dark to work at a screen, from the weather forecast, your camera, or your own threshold.

Straight-line distance between two cities or coordinates, in km, miles, and nautical miles.

GPS coordinates between decimal degrees, DMS, DDM, UTM, and MGRS, with the format detected.

How long a hike will take from distance and climb, by Naismith's rule and Tobler's function, with breaks.

Turn distances on a map into real distances and back, for any scale such as 1:25,000 or 1:50,000.

Crosswind and headwind components for a runway and a wind, with gusts and a diagram. For study, not flight decisions.

The sun's elevation and compass direction for any place, date, and time, with its path through the day.

How long a shadow is from an object's height and the sun's elevation, for any place and time or a given angle.

Find your current coordinates from your device, with degrees, plus code, geohash, and UTM, and open them in a map.

Generate cryptographically random whole numbers within a range.

Generate sorted lottery lines with exclusions and required numbers, and calculate exact match-tier probabilities.

Draw random letters from English, Spanish, French, Greek or Russian Cyrillic, with filters and optional no repeats.

Draw dates between inclusive endpoints, optionally restricted to Monday–Friday, in one of three date formats.

Get an animated random yes or no, optionally include maybe, and keep a short history.

Spin a wheel of names or options to pick one at random: add your own entries or a ready-made wheel, remove the winner, and share the wheel as a link.

Split a list of names into random, even teams, keeping chosen people apart.

Generate an unpredictable-looking string locally in your browser.

Roll one or more dice with cryptographic browser randomness.

Flip one or more virtual coins privately in your browser.

Choose one item at random from a newline-separated list.

Shuffle a newline-separated list into a uniformly random order.

Generate a random hexadecimal color and copy its CSS value.

Printable 75-ball or custom word bingo cards, all different.

Roll any dice notation, such as 4d6kh3, 2d20kh1, 3d6!, or 1d8+3, with the odds of every total.

Pick a random sample of rows from a list or CSV with cryptographic randomness, or a stratified sample by group.

Print numbered raffle tickets with a stub for the buyer's name, your event details, and the price.

Convert a HEX color into RGB and HSL values.

Convert short or long HEX notation into RGB channels.

Convert red, green, and blue channels into HEX notation.

Check two colors against WCAG text contrast thresholds.

See a picture as people with protanopia, deuteranopia, tritanopia, or achromatopsia do, side by side.

Blend two colors by a controlled percentage.

Lighten a color by mixing it with white.

Darken a color by mixing it with black.

Generate the hue-opposite color on a deterministic HSL wheel.

Generate two evenly spaced companions on an HSL color wheel.

Generate neighboring hues 30 degrees to either side of a base color.

Convert a color to grayscale using luminance-inspired sRGB channel weights.

A Tailwind 50–950 palette from one colour, built in OKLCH.

Find the closest CSS colour name to any hex or RGB colour, with a perceptual colour difference.

Any chord's notes, piano keys, and easiest guitar shapes, in all 12 keys, with sound.

Scales and modes in any key on piano and guitar, with chords and playback.

Move a chord sheet to any key with the lyrics untouched, and get a capo suggestion.

Write ABC notation, see an engraved score, play it and export SVG, PNG, MIDI or ABC text.

Build progressions in major, minor, Dorian or Mixolydian with correct note spelling and smooth inversions.

Compose up to four tracks on a piano roll, play or loop them, and save JSON or multi-track MIDI.

Play a sampled grand piano and other sounds with mouse, touch, keyboard, or MIDI, and record as WAV or MIDI.

Tap frets or strum 15 open chords on a physically modelled guitar, and record as WAV or MIDI.

A 17-key kalimba in C with number notation and easy songs, for phone or computer.

A synthesized drum kit to play with taps, keys, or MIDI, recorded as WAV or a General MIDI drum track.

A playable subtractive synth with filter, ADSR, LFO, arpeggiator, presets, and shareable sounds.

Play your guitar through 11 effects in your browser, in any order, with measured latency and recording.

An exact online metronome from 20 to 300 BPM with time signatures, accents, subdivisions, and tap tempo.

Tap a beat with a button or space bar to see rolling tempo and milliseconds per beat.

Note lengths in milliseconds and hertz at any tempo, with dotted and triplet values and tap tempo.

Tune a guitar, bass, ukulele, violin, viola, or cello with your microphone, or any instrument in chromatic mode.

White, pink, and brown noise for sleep and focus, with a fading sleep timer.

Play a sine, square, triangle, or sawtooth tone from 1 Hz to 22 kHz, or a frequency sweep.

Play two slightly different tones, one in each ear, with optional background noise and a timer.

See the live frequency spectrum and a scrolling spectrogram from your microphone, with the loudest note.

Program a 16-step beat with eight synthesised drums, set the tempo and swing, and share it as a link.

Convert a note such as A4 or C#5 to its frequency, or a frequency to the nearest note, with any A4 tuning and a full chart.

An interactive circle of fifths: click a key to see its signature, scale, relative minor, and chords, and hear them.

Practise recognising intervals and chord types by ear, choosing which to include, with a running score.

Play a two-octave xylophone in C by tapping the bars or using the keyboard.

Open a zip file in the browser, preview what is inside, and save the files you need.

Work out what a 3D print costs in filament, electricity, and machine wear, with an allowance for failures and a markup.

Convert 3D printer filament between metres and grams for PLA, PETG, ABS, TPU, and more, in 1.75 or 2.85 mm.

Calibrate a 3D printer extruder: new e-steps from a 100 mm test extrusion, or a new flow rate from a single-wall print.

Open a 3D printer G-code file in the browser and step through it layer by layer, with filament use and print time.

Orbit a local STL or OBJ model, check dimensions and surface area, and estimate volume and PLA mass.

Shutter speed behind an ND filter, by factor or stops, with a long-exposure timer.

Crop factor, equivalent focal length and aperture, and angle of view for any sensor.

Interval, shooting time, clip length, photo count, and card space for a time-lapse.

Sort tasks into do, schedule, delegate, and drop by urgency and importance, then print or copy the matrix.

Score options against weighted criteria and rank them automatically, in an editable table you can copy.

List the pros and cons of a decision, weight each from 1 to 5, and see which way the balance tips.

Type a list with headings, tick it off on screen, or print it with empty checkboxes.

A simple kanban board in your browser: columns, drag-and-drop cards, saved locally, and copy as Markdown.

Make a two- or three-circle Venn diagram with your own labels and items, and download it as PNG or SVG.

Calculate road speed and engine RPM for up to ten gears, from tyre size or diameter.

Calculate cc, litres and cubic inches from bore and stroke, or solve for bore or stroke.

Calculate static compression from engine volumes, with an optional valve-closing geometry estimate.

Estimate quarter-mile ET and trap speed from weight and power, or reverse either result to horsepower.

Lock two camera settings and solve the third for equivalent brightness, with EV and stop tables.

Find a hyperfocal focus distance with editable blur criteria and near and far sharp limits.

Compare 500 and complete NPF shutter estimates, then plan an intentional star-trail stack.