⛽ Gas Station Monitor

⛽ Gas Station Monitor

An independent monitoring tool for the automatic detection of illegal fuel price increases under Germany's 12:00 Rule.

⚖️ The 12:00 Rule (since April 1, 2026)

Since April 1, 2026, a new regulation applies in Germany for fuel prices: gas stations may only raise the price of gasoline or diesel once per day — and exclusively at 12:00 noon (permitted window: 11:30–12:30).

What is permitted?
✓ Price reductions at any time and as often as desired
✓ A single price increase per day, between 11:30 and 12:30
✗ Price increases outside this window (e.g., 8:00 am or 6:00 pm)
✗ Multiple price increases in one day

The goal of the regulation is to eliminate the typical morning and evening price increase cycle and to promote greater price transparency and competition.

April 1, 2026
The 12:00 Rule enters into force
Fine
Up to €100,000 per violation per station (estimate)

🔍 How does the monitor detect violations?

For each price report, the system checks whether it constitutes an increase and whether it falls outside the permitted time window:

  • The new price is compared to the last known price at that station (LAG function over 14 days)
  • If the new price is higher than the previous price, it is an increase
  • If the time is before 11:30 or after 12:30, the entry is flagged as a violation
  • Price reductions are never flagged as violations

Note: Detection is based on the timestamps reported in the Tankerkönig data. Technical delays in price reporting could in individual cases lead to misclassifications. The data does not replace a legal assessment.

📦 Data Sources

All price data comes from publicly accessible, licensed sources:

🛢 Tankerkönig 🗺 OpenStreetMap 📍 Nominatim

Tankerkönig (creativecommons.tankerkoenig.de) is the official price portal of the Market Transparency Unit for Fuels (MTS-K) at the Federal Cartel Office. All gas stations in Germany are legally required to report price changes within minutes. The data is available under the CC BY 4.0 licence.

The map view and postal code search use OpenStreetMap and the geocoding service Nominatim.

~15,000
Gas stations in Germany
since 2014
Historical price data available

❓ Frequently Asked Questions

Where does the price data come from?
From Tankerkönig, the official data service of the Market Transparency Unit for Fuels (MTS-K) at the Federal Cartel Office. All gas stations in Germany are legally required to report price changes within 5 minutes.
How current is the data?
The CSV price data is available daily and stored locally after download. Live prices via the Tankerkönig API are current to within a few minutes.
Are all violations detected?
Detection is based on reported timestamps. If a gas station reports a price change with a delay, this may lead to discrepancies. The monitor evaluates the data as received from the MTS-K.
Is this tool official?
No. This is a private, non-commercial monitoring project. It has no connection to the Federal Cartel Office, the MTS-K, or Tankerkönig.
What happens with a violation?
This monitor documents violations for overview purposes. For an official complaint, contact the Federal Cartel Office (bundeskartellamt.de).

👤 Operator

This project is privately operated by Sebastian Christoph, Bad Salzungen. It pursues no commercial interests.

Imprint · Privacy Policy · Contact: hello@sebastianchristoph.com