---
altdown: 1
canonical: https://altdown.org/
title: Altdown
published: 2026-10-31T00:00:00Z
updated: 2026-10-31T00:00:00Z
lang: en
tokens: 355
tokenizer: cl100k_base
author: Vivek Chopra
signals: search=yes, ai-input=yes, ai-train=yes
generator: altdown.org-gen 0.1
---

# Altdown

An open standard for making web content easier for AI agents to discover and read.

A site publishes a Markdown copy of each page's main content and announces it with one `<link>` element in the page's `<head>`. Agents read what the publisher says the page says, in a fraction of the tokens, instead of guessing from the HTML. An optional index lists every copy, so an agent can discover a whole site at once. Each copy is a plain static file, so a folder of files on any web host can conform.

[Read the specification](https://altdown.org/spec/) [Read it as Markdown](https://altdown.org/spec/index.md)

## Three parts

A site adopts Altdown with three parts. The first two are required. The third is optional.

| Part | What it is | Where it lives | Required |
| --- | --- | --- | --- |
| Markdown copy | One `.md` file per page, with front matter and the page's main content | Next to the page, on the same origin | Yes |
| Link element | One `<link rel="alternate" type="text/markdown">` per page | In the page's `<head>` | Yes |
| Site index | One JSON Feed 1.1 document that lists every copy | Anywhere on the origin, named in `robots.txt` | No |

## In the page's head

```html
<link rel="alternate" type="text/markdown" href="/blog/static-sites/index.md">
```

## At the top of the copy

```markdown
---
altdown: 1
canonical: https://example.com/blog/static-sites/
title: Why we went back to static sites
---
```