Free Online Tools — Nothing to Install, Nothing Leaves Your Browser
Every tool listed here runs entirely in your browser: no sign-up, no installation, and no file uploads to a server. Open a tool, use it, close the tab — that's the whole workflow.
Markdown Editor Online
A full-featured Markdown editor with a live side-by-side preview. Write, format and export without installing anything — useful for README drafts, release notes, or checking how Markdown renders before you publish it anywhere.
Simplified-Traditional Chinese Converter
Convert Chinese text between Simplified and Traditional in real time, with Taiwan and Hong Kong vocabulary variants. Phrase-level conversion via OpenCC dictionaries means ambiguous characters like 发 → 發/髮 land on the right form automatically — and everything runs locally in your browser.
How we pick tools
Only tools that work without an account and without sending your content to a server make it into this collection. Each tool page explains exactly what it does and how to get the most out of it.