extracting-metadata

Extracting metadata

Use this when the user wants structured metadata out of HTML rather than (or in addition to) the Markdown body — page title, description, language, Open Graph tags, structured data, the heading outline, links, or image references.

Metadata lives in result.metadata and is surfaced on the CLI through --json. Metadata is extracted by default; all sub-fields below populate automatically inside result.metadata whenever --json is used. There are no per-field extraction flags.

Get all metadata

html-to-markdown --json input.html | jq '.metadata'

# Extraction-only (skip the Markdown body)
html-to-markdown --json --no-content input.html | jq '.metadata'

Metadata sub-fields

{
  "metadata": {
    "document": { "title": "...", "description": "...", "language": "en", "open_graph": {"title": "..."} },
    "headers": [ { "level": 1, "text": "Main Heading" } ],
    "links":   [ { "href": "https://example.com", "link_type": "external" } ],
    "images":  [ { "src": "photo.jpg", "alt": "A photo", "image_type": "external" } ],
    "structured_data": [ /* JSON-LD, Microdata, RDFa blocks */ ]
  }
}

Metadata flag

There is one metadata flag. The sub-fields above (document, headers, links, images, structured_data) are always populated under result.metadata when --json is set — select what you need with jq.

Flag	Effect
--extract-metadata	(plain-text mode, no --json) emit title + meta tags as an HTML-comment header at the top of the Markdown output

# Pull just the document-level metadata and the heading outline
html-to-markdown --json --no-content input.html \
  | jq '{title: .metadata.document.title, lang: .metadata.document.language, outline: [.metadata.headers[].text]}'

Common queries

# Title + canonical language
html-to-markdown --json input.html | jq '{title: .metadata.document.title, lang: .metadata.document.language}'

# External links only
html-to-markdown --json input.html | jq '[.metadata.links[] | select(.link_type == "external") | .href]'

# Open Graph card
html-to-markdown --json input.html | jq '.metadata.document.open_graph'

# JSON-LD blocks
html-to-markdown --json input.html | jq '.metadata.structured_data'

Programmatic access

from html_to_markdown import convert

result = convert(html)
meta = result.metadata
print(meta.document.title)        # "My Article"
print(meta.document.language)     # "en"
print(meta.headers[0].text)       # "Main Heading"
print(meta.links[0].link_type)    # "external"
print(meta.images[0].alt)         # "A photo"

Metadata is available from the single convert() call in Python, Rust, Go, Ruby, and Elixir; in TypeScript read it off the returned result object. In Rust it requires the metadata feature (on by default).

See ../html-to-markdown/references/cli-reference.md (Metadata section) and ../html-to-markdown/references/configuration.md for field details.