Gadget Hubly

Pick maj7, m7, 9, 11, 13 and more to see the piano keys, notes and degrees — and hear it.

Major, the minor scales, modes, pentatonic, blues. Notes and keys on a piano, played up and down.

Common progressions (Axis, ii–V–I, blues…) plus a builder you can play back in any key.

A precise online metronome powered by Web Audio. Tempo, time signature and accent beat.

Tap along with a track to measure its tempo (BPM). Simple and averaged modes.

Delay and reverb times for every note value, in milliseconds and Hz, from your BPM.

Frequency in Hz for every note, adjustable concert pitch, tap a cell for a reference tone.

Convert bars to playback time and back, from BPM and time signature.

Nyquist frequency, data rate and uncompressed file size for any sample rate.

Live character, word, byte and line counts plus estimated reading time.

UPPER, lower, Title Case, camelCase, snake_case, kebab-case and more in one click.

Convert letters, digits, katakana and symbols between fullwidth and halfwidth.

Beautify, minify, sort keys, and see syntax errors with line and column.

Encode / decode text and Base64. UTF-8 safe, URL-safe option.

Percent-encode / decode, with a query-string breakdown.

Pick a length and character sets. Strong passwords from a cryptographic RNG.

Convert between HEX, RGB and HSL. One-click copy for each code.

Generate random UUID v4 in bulk. Uppercase and no-hyphen options.

SHA-1 / SHA-256 / SHA-384 / SHA-512 of any text, computed live.

Make a QR from a URL or text. Error-correction levels, PNG download.

Length, weight, temperature, area, volume, speed, data size, time.

Unix time ⇄ date, days between, add days, age, Japanese era.

Stopwatch (laps), countdown and Pomodoro in one, with an alarm.

Measure your click count and clicks per second (CPS). Works with touch too.

Click the instant it turns green. Reaction time in ms, average of 5 and personal best.

Dice, coin, number and list picker in one, with an unbiased cryptographic RNG.