Scratch Sheet

A floating, always-on-top spreadsheet sticky note for quick math on Windows. Press a hotkey, work the numbers out with real formulas, press it again and it is gone.

It is for anyone who keeps a spreadsheet tab or the Windows calculator open all day just to add up a few numbers: splitting a bill, checking a quote, totaling an order, working out a percentage.

Download the latest release for Windows 10 or 11 (64-bit). Free and open source under the MIT license.

Why Scratch Sheet

• One hotkey away. Ctrl+Alt+Space shows or hides it from anywhere. After the first launch it starts hidden when you log in and waits in the system tray.
• Real spreadsheet formulas. Hundreds of them (SUM, AVERAGE, IF, ROUND, VLOOKUP, and more), plus number formats, bold and italic, cell colors, borders, merged cells, and conditional formatting, from the Univer spreadsheet engine.
• Types like Google Sheets. Typing $12,133 or 5.7% keeps the number and applies the format, and the arrow keys point at cells while you write a formula.
• Stays out of the way. It has no title bar, floats above your other windows, and remembers its size and position.
• Keeps your work. Every change saves automatically, including your scroll position and active cell, so it reopens exactly where you left off.
• Exports to Excel. Save writes an .xlsx with values, formulas, number formats, bold and italic, font sizes, text and fill colors, borders, merged cells, and column widths.

A scratchpad spreadsheet for Windows

Scratch Sheet is a scratchpad for the numbers you do not need to keep: a running total, a tip split, a quick percentage, a column of figures pasted from an email. Think of it as an always-on-top calculator that shows its work, or a sticky note that understands formulas. Close it and the numbers are still there next time.

Install

1. Download Scratch-Sheet-Setup-<version>.exe from the latest release and run it. It installs for your user account only, so there is no admin prompt.
2. The installer is not code-signed, so Windows SmartScreen may say "Windows protected your PC". Click More info, then Run anyway. Each release's notes list the installer's SHA-256 checksum, so you can check the file before you run it.
3. Open Scratch Sheet from the Start menu once. From then on it starts hidden when you log in.
4. Press Ctrl+Alt+Space to show or hide the sheet.

To update, quit Scratch Sheet from the tray menu, run the new installer, and start it from the Start menu.

Using it

• Show or hide: press Ctrl+Alt+Space, or left-click the tray icon.
• Move: drag the rounded tab in the bottom-right corner, or hold Ctrl and drag anywhere on the sheet. Resize from any edge.
• Corner strip (top right): the pin keeps the sheet on top of other windows, the sun or moon switches between dark and light mode, Clear empties the sheet in one click (Ctrl+Z brings it back), Save exports an .xlsx, and × hides the sheet to the tray.
• Three tool circles (bottom right): drag them anywhere as a group. Each one opens its own set of tools.
  • The palette: smaller and larger text, text color, and fill color.
  • 123: format painter, percent, currency, date, fewer decimals, and more decimals.
  • The grid: conditional formatting, borders, and merge cells.
• Format painter: select a cell, click the brush in the 123 tools, then click another cell to copy the formatting onto it. Double-click the brush to keep painting, and press Esc to stop.
• Right-click a cell: Number format (Automatic, Number, Percent, Currency, Currency (rounded), Date, Time, Date time, Plain text) and Align (Left, Center, Right).
• Keyboard: Ctrl+B bold, Ctrl+I italic, Ctrl+Z undo, Ctrl+Y redo.
• Tray menu (right-click the tray icon): Show / Hide, Always on top, Dark mode, Launch at startup, Open data folder, Edit config, and Quit. Closing only hides the sheet. Quit is in the tray menu.

Change the hotkey

Right-click the tray icon, choose Edit config, and change hotkey using Electron accelerator syntax (for example Control+Shift+F12). Save the file, quit from the tray, and start Scratch Sheet again. If another app already owns the combo, Scratch Sheet shows a warning when it starts.

Use a Logitech G key

G keys only send what G HUB assigns to them, so map a G key to the combo Ctrl+Alt+Space in G HUB.

Your data

• The sheet and settings are stored in %APPDATA%\Scratch Sheet\: sheet.json holds the sheet, and config.json holds the hotkey, theme, window position, and the Always on top and Launch at startup settings. Open data folder in the tray menu goes straight there.
• There is no account or sign-in.
• The folder is kept through updates and uninstalls. To remove your data for good, delete it after uninstalling.

Uninstall

Open Settings > Apps, find Scratch Sheet in the list of installed apps, and choose Uninstall. Your sheet stays in %APPDATA%\Scratch Sheet\ (see Your data).

Scope

Scratch Sheet deliberately stays small:

• One sheet, with no tabs. It does not open files; Save exports a copy.
• Text alignment and conditional formatting rules stay in the app and are not written to the .xlsx.
• Windows only.
• No automatic updates. New versions are posted on the Releases page, and changes are listed in CHANGELOG.md.
• The installer is not code-signed.

Build from source

You need Windows and Node.js 22.12 or later.

npm install          # installs dependencies and applies the Univer patch in patches/
npm run build        # builds the app and the installer: release\Scratch Sheet Setup <version>.exe

For development:

npm run dev          # builds the renderer and starts the app with electron .
npm run build:dir    # unpacked build in release\win-unpacked (no installer)
npm test             # DevTools Protocol smoke test against an instance started with --remote-debugging-port=9222
# QUIET=1 never shows the window (skips right-click steps); CDP_PORT picks another port;
# SCRATCH_DATA=<dir> checks the sheet.json of an instance started with --user-data-dir=<dir>

electron/main.js     window, tray, hotkey, IPC, login item
electron/preload.js  contextBridge API exposed as window.scratch
electron/export.js   snapshot -> .xlsx (ExcelJS), pure Node
src/                 renderer: Univer grid, toolbar, autosave
patches/             fix for Univer's arrow keys wrapping at the sheet edges (applied by patch-package)
build/make-icon.js   generates build/icon.png with no dependencies
test/                CDP smoke and restart tests

Credits

Built with Electron, Univer, ExcelJS, Vite, electron-builder, patch-package, and Material Symbols icons by Google. The full list of bundled packages and their licenses is in THIRD-PARTY-NOTICES.md.

License

MIT. See LICENSE. Made by sleetcrash.