XML to Flow Converter
Generate Flow types from XML instantly. Optional fields are detected automatically. Runs entirely in your browser.
Input
Output
Ready
Drop a file to load it
About this tool
Paste an XML sample and get Flow type definitions you can use immediately. Emits exact object type aliases with a `// @flow` pragma.
When you would use it
- A JavaScript codebase typed with Flow rather than TypeScript
- Bootstrapping models from a real XML response instead of writing them by hand
- Keeping types in step with an API that has changed
Worked example
<?xml version="1.0" encoding="UTF-8"?>
<user id="4815">
<name>Ada Lovelace</name>
<active>true</active>
<score>91.5</score>
<roles>
<role>admin</role>
<role>editor</role>
</roles>
</user>
// @flow
export type Root = {
user: User,
};
export type User = {
@id: number,
name: string,
active: boolean,
score: number,
roles: Roles,
};
export type Roles = {
role: string[],
};
Things worth knowing
- Every object in an array is merged when inferring the shape, so a field missing from one item is marked optional rather than assumed to always be present.
- Identical nested shapes are de-duplicated into a single type instead of generating near-duplicates.
- Array element types are named from the singular of the field name, so
postsproduces aPosttype. - XML carries no type information, so numeric and boolean-looking text is inferred. Check the result where a value could legitimately be a string.
Questions
Frequently asked
How are optional fields detected?
By comparing every object in an array. A key present in some records but not others becomes optional; a key present in all of them is required. This is why passing several records gives better results than one.
Can it handle deeply nested XML?
Yes. Nested objects become separate named types, referenced from their parent, at any depth.
Is my data uploaded anywhere?
No. Every tool on JSONWorks runs entirely in your browser using JavaScript. Your input is never sent to a server, never logged and never stored. The simplest proof is to disconnect from the internet — the tools keep working. The site does load Google Fonts and a Google Analytics page-view tag, so you will see those two requests in your network tab, but neither receives anything you type or paste.
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