Spec v1.0 · Open Standard · CC BY 4.0

Make real estate
readable
by machines.

One file. One standard. Every AI can find and understand your property. Drop a property.txt on any website — and let LLMs, search agents, and tenants discover it directly.

Try the AI Matcher ↓ Read the Spec

property.txt

Core Sections

0€

To Implement

Compliant by Design

∞

AI Agents Can Parse

The Manifesto

Real estate is trapped
in walled gardens.

Tenants search five platforms. Landlords list on three. Nobody's data talks to anybody else. And the new wave of AI assistants? They can't read any of it.

Property DNA changes this. It's an open, machine-readable format — like robots.txt, but for real estate. Host it on your website. Let AI find your property. Skip the portals. Own your listing.

Problem 01

Data Silos Kill Reach

ImmoScout, Willhaben, ImmobilienScout — none share data. Your listing exists in isolated databases that AI can't access.

Problem 02

AI Can't Crawl Listings

ChatGPT, Perplexity, Claude — they understand text, not portal HTML. There's no structured format for them to read.

Problem 03

Tenants Are Exhausted

The average apartment search spans 5+ platforms, dozens of tabs, and weeks of manual comparison. It's broken.

How It Works

Four steps to an AI-native listing.

No portal needed. No subscription. Just a text file, a link tag, and a ping.

Create your property.txt

Describe your property in structured YAML — with photos. Or let SusiSorglos generate it from your existing data.

Host it on your website

Upload to yoursite.com/property.txt and add a <link rel="property-dna"> tag to your HTML head.

Ping the registry

Send a single POST to ping.propertydna.org — your listing gets validated and added to the global index.

AI discovers & matches

LLMs and AI assistants find your listing via the registry, parse it, and surface it in conversations — with photos.

The Specification

Seven sections that describe any property, completely.

Every field is objective, measurable, and EU-compliant. No tenant profiling. The spec describes the property, never the person.

📍

Identity

Address, type, status, coordinates

📐

Specifications

Size, rooms, features, layout

💶

Financials

Rent, deposit, costs, commission

⚖️

Compliance

Energy class, legal, building

🗺️

Context

Transport, neighborhood, community

📸

Media

Photos, floorplans, virtual tours

🔍

Discovery

How crawlers find your file

Discovery

Three ways AI finds your property.

Just hosting the file isn't enough. Crawlers need to know it exists. Use one or more of these methods.

METHOD 1

HTML Link Tag

Add a <link> tag to your website's <head>. AI crawlers and search engines pick it up automatically.

<!-- In your <head> -->
<link rel="property-dna"
      href="/property.txt"
      type="text/plain" />

<!-- Multiple properties? -->
<link rel="property-dna"
      href="/properties/unit-1.txt" />
<link rel="property-dna"
      href="/properties/unit-2.txt" />

METHOD 2

robots.txt Entry

Add a Property-DNA directive to your existing robots.txt. Crawlers already check this file.

# robots.txt
User-agent: *
Allow: /

# Property DNA discovery
Property-DNA: /property.txt
Property-DNA: /properties/unit-2.txt

METHOD 3

.well-known Endpoint

For portals with many listings: serve a JSON index at /.well-known/property-dna that lists all property files.

// GET /.well-known/property-dna
{
  "version": "1.0",
  "properties": [
    "/properties/AT-1060-GUMPENDORFER.txt",
    "/properties/AT-1020-PRATER.txt"
  ],
  "updated": "2026-02-21T10:00:00Z"
}

Ping Registry

Ping your domain to ping.propertydna.org and your listings get indexed for every AI agent worldwide.

HOW IT WORKS

One POST. Globally indexed.

When you publish or update a property.txt, send a single API call. The registry crawls your file, validates it, and adds it to the master index.

# Register a single property
POST https://ping.propertydna.org/v1/ping

{
  "url": "https://example.com/property.txt",
  "event": "publish"
}

# Response
{
  "status": "indexed",
  "id": "AT-1060-GUMPENDORFER-12-TOP3",
  "validation": "LEVEL 3 — COMPLETE",
  "next_crawl": "2026-02-22T10:00:00Z"
}

Ping your domain

Events

publish— New listing or first-time registration

update— Price, status, or data changed

unpublish— Property rented/sold, remove from index

Who uses the index?

AI providers (OpenAI, Anthropic, Google) can query the registry to discover all Property DNA files worldwide — making your listing visible to every AI assistant, everywhere.

Tools

Validate, match, and experience the standard.

Test your property.txt, or let our AI match tenants against real listings — live.

Wonach suchst du?

◇

4 property.txt Dateien geladen.
Starte eine Suchanfrage oder klicke einen Beispiel-Query.

Validation Results

◇

Paste your property.txt and hit validate

Paste property.txt

Inserat-Text einfügen

Kopiere den Text eines Inserats von Willhaben, ImmoScout, Immowelt oder einer anderen Plattform — die AI generiert daraus eine property.txt

Generierte property.txt

↻

Inseratstext einfügen und
umwandeln klicken.

OpenImmo XML importieren

Lade eine OpenImmo-XML-Datei hoch — der Parser extrahiert alle Immobilien und konvertiert sie automatisch in das property.txt Format.

⬆

XML-Datei auswählen oder hierher ziehen

OpenImmo 1.1 – 1.2.7

Oder XML direkt einfügen

Konvertierte Properties

⬆

OpenImmo XML hochladen
oder einfügen.

ChatGPT Custom GPT

Deploy your own AI-powered property matcher in 5 minutes.

Copy-paste these fields into the ChatGPT GPT editor. Replace the sample properties with yours. Share the link.

Name & Description

Go to chat.openai.com/gpts/editor → "Configure" tab → paste:

Name: Property DNA — Wohnungssuche mit AI

Description: Finde deine perfekte Wohnung. Beschreibe was du suchst — ich matche dich gegen verfügbare Immobilien im Property DNA Standard. Kein Portal-Hopping, kein Rätselraten.

System Prompt (Instructions)

This is the brain of your GPT. Paste the entire block into the "Instructions" field. Then replace the sample properties at the bottom with your own property.txt data.

Conversation Starters

Add these as conversation starters so users can jump right in:

Ich suche eine Wohnung in Wien — kannst du mir helfen?
Was habt ihr für Familien mit Kindern?
Zeig mir alles unter €1100 mit guter Öffi-Anbindung
Ich brauche eine ruhige Wohnung mit Garten für mich und meinen Hund

Share & Distribute

After publishing, you get a share link. Use it everywhere:

• Website: "AI-Wohnungssuche starten" Button → Link to GPT
• Inserate: Add GPT link to listing description
• WhatsApp/Email: Send link to interested tenants
• QR-Code: Print on "Zu Vermieten" signs
• Social Media: Post as interactive apartment search

Pro tip: 5-20 properties per GPT = optimal context.
20+ properties → split into multiple GPTs or use SusiSorglos Pro API.

Adoption Path

Open standard. Clear path to monetization.

The spec is free forever. The tools around it create value.

Free · Open Standard

Spec + Validator

Full specification, validation tools, and documentation. Free to implement, forever. CC BY 4.0.

FREE

Pro · SusiSorglos

Auto-Generate DNA

Import your listings and auto-generate Property DNA files. Hosted, synced with your property management.

from €9/mo per property

Enterprise · API

Bulk Parse & Validate

API endpoints for portals and platforms. Validate, parse, and index Property DNA files at scale.

Custom Pricing

Ecosystem · Plugins

WordPress, Wix & more

One-click plugins to generate and host property.txt. No technical knowledge required.

Coming Soon

Make real estatereadableby machines.

Real estate is trappedin walled gardens.