AI-assisted JS to TS conversion
Converts pasted JavaScript into TypeScript with type annotations, interfaces, generics, and inferred types.
JS2TS
Freemium
JS2TS converts JavaScript to TypeScript with AI for faster code migration, plus TypeScript, Zod, and JSON conversion tools.
What is JS2TS?
JS2TS is an online converter for JavaScript-to-TypeScript migration. It uses AI to turn pasted JavaScript into typed TypeScript by adding annotations, interfaces, generics, and other type constructs that fit the input code.
The site positions the tool as a quick way to reduce manual migration work: instead of renaming files and adding types by hand, users paste code, convert it, and copy the TypeScript output. The same site also offers adjacent tools for TypeScript to JavaScript, TypeScript to Zod, and JSON to TypeScript conversions.
What can JS2TS do?
Broad TypeScript syntax coverage
Supports common migration patterns including function parameters and return values, object shapes, arrays, unions, intersections, classes, async code, and module syntax.
Fast browser-based workflow
Provides a simple paste-and-convert workflow with instant output in the browser.
Reverse conversion tool
Offers a separate TypeScript to JavaScript converter for stripping TypeScript-specific syntax back to plain JavaScript.
Related conversion tools
Includes adjacent converters such as TypeScript to Zod and JSON to TypeScript for related developer workflows.
No-login, real-time processing
States that conversions are processed in real time and not stored on the server.
Use Cases
“Migrate JS projects to TypeScript”
Convert existing JavaScript files into typed TypeScript when you want faster migration than doing the annotations by hand.
“Work with React and Node.js code”
Transform React components and Node.js modules into typed output that better fits larger application codebases.
“Convert TypeScript to JavaScript”
Strip TypeScript syntax back to plain JavaScript when you need code that can run without a TypeScript compiler.
“Derive validation schemas from types”
Generate Zod schemas from TypeScript interfaces when you need runtime validation in addition to compile-time types.
“Create TypeScript interfaces from JSON”
Turn JSON into TypeScript interfaces when starting from API responses or structured data payloads.
Frequently Asked Questions
How do I convert JavaScript to TypeScript?
Paste JavaScript into the converter, click Convert, and copy the TypeScript output. The tool automatically adds type annotations, interfaces, and generics.
Is the JavaScript to TypeScript converter free?
Yes. The site states that the JavaScript to TypeScript converter is completely free and does not require an account, login, or credit card.
What kinds of TypeScript patterns does JS2TS support?
The converter handles common patterns such as function parameter and return types, object interfaces, arrays, unions, intersections, generics, class property types, async return types, module imports and exports, React props, and type inference from usage.
Does JS2TS store my code?
The site says conversions are processed in real time and your code is never stored or logged on its servers.
Does JS2TS work with React and Node.js code?
Yes. The site says it works with React components, Node.js modules, ES6+ syntax, CommonJS, and ESModules.
Quick Facts
- Category
- Developer Tool
- Platform
- Web app
- Primary use
- JavaScript to TypeScript conversion
- Source domain
- js2ts.com
- Pricing
- Free online tool
- Related tools
- TypeScript to JavaScript, TypeScript to Zod, JSON to TypeScript
JS2TS Traffic Analysis
Traffic data is for reference only.
- Domain Rating
- 10
JS2TS Alternatives
LiveKit
livekit.io
LiveKit is an open source platform for building, deploying, and observing voice, video, and physical AI agents with Python or TypeScript, plus LiveKit Cloud for production.
Refraction
refraction.dev
AI code generation for refactoring, tests, docs, bugs, and code conversion
PearAI
trypear.ai
Open-source AI code editor with chat, agentic coding, and model routing, plus free, Maker, and Enterprise plans.
WPTurbo
wpturbo.dev
WordPress code generator and snippet manager for faster reusable code
Postfleet
postfleet.ai
Postfleet is email infrastructure for AI agents that screens inbound messages, sanitizes content, and extracts clean mail into typed JSON before agents read it. Supports hosted and local MCP access, plus REST for non-MCP workflows.
Paybond CLI
paybond.ai
Paybond CLI sets up safe agent spend flows with sandbox login, guardrails, MCP configuration, diagnostics, and JSON automation for TypeScript and Python.