Convert bits, bytes, kB, MB, GB, KiB, MiB, GiB, and more.

Find years, months, days, total days, and weeks between dates.

Get the total days between two dates, with inclusive and exclusive counts.

Solve density, mass, or volume with unit conversion.

Find final price and savings after a percentage discount.

Calculate PWM duty cycle, pulse width, frequency, period, and off-time.

Convert J, kJ, MJ, Wh, kWh, cal, kcal, and BTU.

Solve force, mass, or acceleration with F = ma.

Calculate and simplify arithmetic with two fractions.

Convert km/L, L/100 km, US mpg, and UK mpg.

Calculate GCD and LCM for two whole numbers.

Solve gravitational potential-energy change, mass, or height.

Generate SHA-2 hashes for text and files locally.

Inspect an HTML heading outline and spot skipped levels.

Convert text to and from HTML entities directly in your browser.

Parse and inspect raw HTTP header fields locally.

Combine inductors in series or parallel and calculate reactance.

Inspect IPv4 networks and CIDR ranges without sending addresses to an API.

Parse and create ISO 8601 date/time values.

Validate JSON, pretty-print it, minify it, and inspect JSON paths.

Convert between JSON arrays and JSON Lines / NDJSON.

Navigate JSON with standard slash-separated JSON Pointers.

Infer TypeScript types from JSON sample data.

Inspect JWT header, payload, and time claims locally.