API Documentation

Use our API to integrate HWP conversion into your applications. All endpoints are free to use with no authentication required.

Base URL

https://hangul.io

Endpoints

1. Convert to JSON (Recommended)

Returns the converted content as JSON. Supports both file uploads and URL-based conversion.

POST /api/convert-json?format={markdown|html}

Parameters:

format (query): markdown or html (default: markdown)

Request Body (File Upload):

multipart/form-data
file: [HWP file]

Example (File Upload):

curl -X POST https://hangul.io/api/convert-json?format=markdown \
  -F "file=@document.hwp"

Request Body (URL):

{
  "url": "https://example.com/document.hwp",
  "format": "markdown"  // optional, can also use query param
}

Example (URL-based):

curl -X POST https://hangul.io/api/convert-json?format=markdown \
  -H "Content-Type: application/json" \
  -d '{"url": "https://example.com/document.hwp"}'

Response:

{
  "success": true,
  "markdown": "# Document Title\n\nContent..."
}

Or for HTML:

{
  "success": true,
  "html": "<!DOCTYPE html><html>...</html>"
}

2. Convert and Download Files

These endpoints return the converted file directly for download.

POST /api/convert

Upload HWP file, download Markdown file

POST /api/convert-url

Convert from URL, download Markdown file

POST /api/convert-html

Upload HWP file, download HTML file

POST /api/convert-url-html

Convert from URL, download HTML file

Example:

curl -X POST https://hangul.io/api/convert \
  -F "file=@document.hwp" \
  -o output.md

Limits & Requirements

Maximum file size: 50MB
Supported formats: HWP 5.x (including distribution format 배포용)
Rate limits: None currently, but subject to change for abuse prevention
Authentication: Not required

Error Responses

{
  "error": "Error message description"
}

Common errors:

400: Invalid file type, no file provided, or invalid URL
500: Conversion failed or server error

Support & Contact

For high-volume usage, custom integrations, or support questions, please contact us at hello@hangul.io