---
title: "06 Variables and Filters"
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# Web Clipper: Variables and Filters

**Variables** pull data out of a page. **Filters** reshape it. Together they are how a template turns a web page into the document you actually want.

## Preset variables

Automatically pulled from every page:

| Variable | What it gives you |
| --- | --- |
| **title** | The page title |
| **author** | The author, where the page declares one |
| **description** | The page description |
| **published** | The published date |
| **domain** | The site's domain |
| **url** | The full URL |
| **content** | The extracted article content |
| **highlights** | Your saved highlights |
| **selection** | The text you had selected |
| **image** | The social/share image |
| **word count** | The length of the article |

## Meta variables

Read any `<meta>` tag or **Open Graph** tag from the page. Anything the page tells crawlers about itself, you can use.

## Selector variables

Extract **any element's text or HTML** using a **CSS selector**.

This is the escape hatch. When a page holds something no preset covers — a price, a rating, a byline in an unusual place — a selector gets it. It is also the most fragile approach, since it breaks when the site changes its markup. Prefer schema.org or meta variables where they exist.

## Schema.org variables

Read the **structured data** embedded in the page. Many sites publish rich, reliable schema.org data — recipes, products, articles, events — and reading it is far more robust than scraping the rendered HTML.

If a page has schema.org data, use it. It is the most stable source available.

## Filters

A large library transforms variable values:

- **Date formatting.**
- **Case conversion.**
- **Markdown conversion** — turn extracted HTML into clean markdown.
- **List, table and callout formatting** — turn an array into a bulleted list, a table, or a callout block.
- **Math.**
- **Array and object manipulation** — map, filter, join, pick.
- **HTML cleanup.**

Filters chain, so you can take a raw value, clean it, reshape it, and format it in one expression.

## Debugging

**Inspect the page variables** available for templates before clipping. It shows what the page actually exposes on *this* page.

When a template produces something wrong, this is the first place to look. Usually the variable you assumed exists simply is not there — the page never declared an author, or the published date is in an unexpected format.

## A practical approach

1. **Inspect the variables** on a page you clip often.
2. Prefer **schema.org**, then **meta**, then **selectors** — in that order of robustness.
3. Add **filters** to tidy the output.
4. Reach for a **prompt variable** ([08 AI Interpreter](/doc/4083577d-96da-4ee2-8e3b-1faee2410775)) only when the information genuinely is not in the page's data — a summary, a judgement, a categorization. Do not use a language model to extract something a meta tag already states exactly.