HTML Clay

Simple Apps. One File.

A whole app in one local HTML file. Anyone can make one, because it's just HTML.

Download
Free. No account. Works offline.

A file you own

One file, start to finish

Email it, back it up, drop it in any folder. No account, no cloud, no app store. The file is the whole app, and it belongs to you.

Your changes stick

Jot a note, check a box, drag things around. It saves itself right back into the file. Reopen it next week and it's exactly as you left it.

Quiet and private

It runs entirely on your computer. No sign-up, no tracking, nothing leaves your machine. It even works on a plane.

How it works

Install HTML Clay

One small, free app. One time.

Double-click a file

Any .htmlclay file opens in your browser, in an ordinary tab. Same browser you already use, same shortcuts.

Just use it

Type, edit, organize. Changes go back into the same file, and most files save as you go.

It's just a web page

Rename it .html and it opens in any browser. HTML Clay only adds one thing: the ability for the page to save your edits back into the file.

What people make

Is it safe?

As safe as a web page. It runs in your browser's sandbox, and a page saves only into its own file. The one exception is a folder you explicitly trust: inside it, any HTML Clay file can change any other, which is what makes a project of linked documents work. Nothing outside your home folder opens at all. The one real risk is the same anywhere online: be cautious if a page asks you to download and run a separate program.

The long version of everything the app does, with this boundary stated exactly, is on the features page.

Download v1.8.1

macOS Universal (Apple Silicon + Intel), signed and notarized
HTMLClay-1.8.1-universal.dmg 1186f4664cb19e2c3d531bd40a713e9607ed9c1012e6d13241760ba3324625a6
Windows 64-bit Intel or AMD, signed
htmlclay-windows-amd64.zip bd5d0dabc23b406f4de09e8bb00d6ae6d2e73d3dce442601dbf577b52f333eba
Windows ARM64, signed
htmlclay-windows-arm64.zip ace0fcff0aea6219f7bc74d9623aed4780d41b4aa30a04d6107e62b4fe0268e3
Linux x86_64
htmlclay-linux-amd64.tar.gz 44a9fa5fab894892dc5170282b4239b0f43301dcae96ecd6d8843d37922d454f
Linux ARM64
htmlclay-linux-arm64.tar.gz 7fb9c0a60c5aa08fe88df0c2701cc9fb4fc772b8c02dd169371766d47cfc608d

Opening it. On macOS, drag it into Applications. On Windows, unzip it and run htmlclay.exe once: it sets up .htmlclay files for your account, with no administrator prompt. On Linux, unpack the tarball and run bash install.sh, which installs into ~/.local/bin and never asks for sudo.

One thing Linux needs. Permission prompts are real desktop dialogs, drawn by zenity or kdialog. With neither installed, a file opened from outside a folder you trust is refused rather than asked about. Folders you trust work either way.

Checking what you downloaded. Every file's SHA-256 is listed in SHA256SUMS. Hash your copy and compare it with the matching line: sha256sum <file> on Linux, shasum -a 256 <file> on macOS, certutil -hashfile <file> SHA256 on Windows.

The simplest way to make and run software.