TypeScript Transpiler
Convert TypeScript snippets to best-effort JavaScript in your browser. The tool strips type-only syntax locally in WebAssembly without running a full compiler.
What this tool does
This tool turns small TypeScript snippets into best-effort JavaScript by removing syntax that only exists for the type system. It strips annotations, interfaces, type aliases, as/satisfies assertions, optional markers, access modifiers, implements clauses, type-only imports/exports, and simple enum declarations.
The conversion runs locally in WebAssembly. It is useful for examples, docs, playground snippets, and quick migrations where you want readable JavaScript without starting a full TypeScript compiler.
Example
Input:
type User = { name: string }
export function greet(name: string): string {
const label: string = name as string;
return `Hello ${label}`;
}
Output:
export function greet(name) {
const label = name;
return `Hello ${label}`;
}
Options
| Option | Choices | What it does |
|---|---|---|
| Enum handling | compile (default), strip | Converts simple enums into JavaScript objects, or removes enum declarations entirely. |
| Remove comments | off (default), on | Removes // and /* ... */ comments after normalizing line endings. |
Limits and edge cases
This is a deterministic syntax stripper, not the official TypeScript compiler. It does not type-check, resolve modules, inline const enum, transform namespaces, emit decorator metadata, rewrite JSX, downlevel modern JavaScript, or guarantee correct output for every legal TypeScript program. For production builds, use tsc, Babel, SWC, or esbuild.
The input limit is 1 MB. The output preserves most original formatting, so already-minified input stays compact.
FAQ
Is this the same as running tsc?
No. tsc parses the whole TypeScript language, type-checks when requested, resolves project settings, and can downlevel JavaScript. This tool is a fast local syntax stripper for snippets and simple files.
Does it support interfaces and type aliases?
Yes. Interface and type alias declarations are removed because they have no JavaScript runtime representation. References to those types in annotations are removed with the annotation.
What happens to enums?
By default, simple numeric enums are converted to JavaScript objects. If you choose strip, enum declarations are removed instead. Complex enum initializers are copied as object values but are not evaluated.
Can I use the output in production?
Use it as a preview or migration helper, then run your normal compiler and tests. The tool deliberately documents unsupported TypeScript features rather than pretending to be a complete compiler.
Developer & Automation Access
Run it from the terminal
Same engine as this page, headless — via the gizza CLI:
gizza tool typescript-transpiler 'type User = { name: string }
export function greet(name: string): string {
return `Hello ${name}` as string;
}'New to the CLI? Get gizza →
Open it by URL
Pre-fill and auto-run this tool with query parameters — the names match the API/CLI:
https://gizza.ai/tools/typescript-transpiler/?input=type%20User%20%3D%20%7B%20name%3A%20string%20%7D%0Aexport%20function%20greet%28name%3A%20string%29%3A%20string%20%7B%0A%20%20return%20%60Hello%20%24%7Bname%7D%60%20as%20string%3B%0A%7D&enum_style=compile&remove_comments=trueMachine-readable descriptor: tool.json — title + parameters JSON Schema for agents.