Open .TS files online
A .ts file contains TypeScript source — a typed superset of JavaScript created by Microsoft that compiles to plain JavaScript. TypeScript adds static types, interfaces, and better tooling, which has made it the default for large web applications and many libraries.
TypeScript types are erased at compile time: the output that runs is ordinary JavaScript. The .ts source is what you read to understand the intended shapes and contracts of the code, which is why inspecting it is so useful when working with a typed codebase.
What is a `.ts` file?
TypeScript lets you annotate variables, parameters, and return values with types, define interfaces and type aliases, and use generics. A tsconfig.json controls compilation targets and strictness. The compiler type-checks and then strips the types to emit JavaScript.
A .ts file is plain text (UTF-8). It cannot run directly in a browser or Node — it must be compiled (or transpiled on the fly by a runtime like Deno or tsx).
- Large web applications (React, Vue, Angular)
- Type-safe Node.js services and CLIs
- Shared libraries with published type definitions
- Any project that wants compile-time error checking
How to open a `.ts` online
Open the zip viewer in a new tab, then drop your .ts onto the page — or click to browse for it, or paste a URL. The file opens in the Monaco code editor, with syntax highlighting, code folding, and find, read entirely on your device.
- Drag your
.tsonto the page — or click to browse, or paste a URL. - It opens immediately in the Monaco code editor, with syntax highlighting, code folding, and find. No install, no sign-up.
- Read, search, or copy it. Your file never leaves your browser.
Open `.ts` without uploading
Most "open ts online" sites work by uploading your file to a server and processing it there. ZipTool does the opposite: it loads its parser once, then reads your .ts locally in the browser tab. The contents stay on your device.
You can prove that in seconds. Open the page, press F12 for DevTools, switch to the Network tab, and open your file — no request carrying the file's contents is sent. You can also turn off Wi-Fi after the page loads and the file still opens. See security and privacy for the full picture.
Frequently asked questions
How do I open a .ts file online?
Drag the .ts onto the page (or click to browse, or paste a URL). It opens in the code editor so you can read the types and logic, search, and copy — it is not compiled or executed. The file is parsed entirely in your browser and never uploaded.
Can I view a .ts without uploading it?
Yes. ZipTool reads the file locally in your browser tab — no upload, no server-side copy. Confirm it with DevTools (F12, Network tab) while opening the file, or by disabling Wi-Fi after the page loads and verifying the file still opens.
Can a browser run a .ts file directly?
No — browsers run JavaScript, not TypeScript. A .ts must be compiled to .js first (some bundlers and runtimes do this automatically during development). The viewer shows the source; it does not compile or run it.
What is the difference between TypeScript and JavaScript?
TypeScript is a typed superset of JavaScript. Any valid JavaScript is valid TypeScript, but TypeScript adds optional static types that are checked at compile time and then removed. The type information helps catch errors early and powers better editor tooling; the shipped output is plain JavaScript.