Skip to content
AppBox
Version 3.0.0 — 36 tools

Every small tool you need, in one fast app

Calculators, converters, developer utilities, timers, finance and health tools — 36 of them, all free. No signup, no API keys, nothing uploaded, and almost all of it works with no internet at all.

Open the calculatorSource on GitHub

Press ⌘K anywhere to jump to a tool

Works offline

34 of 36 tools need no connection at all. Install it once and it keeps working on a plane.

Stays on your device

No accounts, no analytics, no uploads. Notes, todos and everything you type live in your browser storage.

Instant to load

A static site with per-tool code splitting, so opening a tool loads that tool and nothing else.

No API keys

Even weather and currency work out of the box. Nothing to sign up for, nothing to configure.

Most used

The tools people open first.

CalculatorFree online calculator with basic and scientific modes, full keyboard support, and a running history you can reuse.Unit ConverterConvert length, weight, temperature, area, volume, speed, time, data, pressure and energy between 90+ units.Clock, Timer & StopwatchA live clock, a countdown timer with an audible alert, and a lap stopwatch accurate to hundredths of a second.JSON Formatter & ValidatorFormat, minify and validate JSON with precise error positions, sorted keys and a collapsible tree view.Todo ListA fast, private task list with priorities, due dates, filters and drag-free reordering. Saved on your device.Weather ForecastCurrent conditions and a 7-day forecast for any city worldwide. No API key required, and cached for offline use.

All 36 tools

Grouped by what they do. A dot marks the two that need a connection.

Also a desktop app

The same 36 tools ship as a native app for Windows, macOS and Linux — a real window with its own menu bar and keyboard shortcuts, and no browser tab in the way. Or install this page as an app straight from your browser.

Download for desktop