A man used AI to call 3,000 Irish bartenders to track the cost of Guinness. Now pubs are lowering their prices to compete

In an innovative move that has caught the attention of both consumers and the pub industry, Matt Cortland, a 37-year-old entrepreneur, utilized artificial intelligence (AI) to track the price of a pint of Guinness across Ireland. After experiencing a shockingly high price of €7.80 (approximately $8.93) for his favorite drink in Dublin, Cortland decided to take matters into his own hands.

The Birth of the Guinndex

Frustrated by the lack of price tracking for Guinness, which had been discontinued by the Central Statistics Office in 2011, Cortland devised a plan to gather this information himself. As the founder of an AI startup, he leveraged AI technology to create a voice agent named Rachel, utilizing ElevenLabs’ voice generation platform. Rachel, who sports a Northern Irish accent and is named after a contestant from the reality TV show “The Traitors,” made over 3,000 calls to pubs across Ireland, inquiring about the price of a pint of Guinness.

The Process

Cortland’s approach was straightforward yet ambitious. He thought, “Can I just call every pub in Ireland and conversationally ask them with AI?” After pulling on this thread of curiosity, he began to compile data from the thousands of phone calls made by Rachel. The information collected was then analyzed using Anthropic’s Claude AI to create the “Guinndex,” a dynamic consumer price index for Guinness.

Current Pricing Insights

As of the latest data, the average price of a pint of Guinness in Ireland stands at approximately €6.01 (around $6.88), with the most common price being €5.50 ($6.30). This information is crucial for consumers who want to ensure they are not overpaying for their drinks.

Impact on Pubs

While the Guinndex has not yet caused dramatic shifts in pricing, it has already begun to influence pub owners. Cortland reported that one pub owner voluntarily lowered the price of Guinness by €0.40 after updating the Guinndex with their new pricing. This transparency in pricing is essential in a market where prices can vary significantly, sometimes by as much as €2 between pubs located just a short distance apart.

AI’s Role in Consumer Transparency

The use of AI in this context is not only innovative but also highlights the growing trend of using technology to solve everyday problems. AI models are advancing rapidly, and while some fear the implications of AI on job markets, others see it as a tool for enhancing consumer awareness and choice.

Consumer Interaction with AI

Data from voice AI firms indicate that customers are increasingly finding AI agents credible. In fact, studies show that people spend 14% more time interacting with AI than with human representatives, often providing longer responses and sharing more details. Cortland’s experience mirrored these findings, as many bartenders were unaware they were speaking with an AI agent during their conversations.

Real Conversations

Some of the transcripts from Rachel’s calls reveal the friendly nature of the interactions:

• A bartender at Doogies in Enniskillen, Northern Ireland, humorously stated, “The cost of a pint of Guinness? Twenty-five pounds. But if you’re coming in for a wee drink, I’ll give it to you for a fiver.”
• An employee at Malzards Pub in Kilkenny offered, “Listen, they’re normally 6.20 [euros], but if you can’t afford one, we’ll buy you one. We’ll look after you.”

Future Aspirations

Looking ahead, Cortland hopes to replicate the success of the Guinndex for other products, potentially expanding to areas such as prescription drug pricing in the U.S. or even the cost of a slice of pizza in New York City. He emphasizes the importance of consumer awareness in markets where prices can fluctuate wildly.

Conclusion

As the Guinndex continues to evolve, it serves as a testament to the power of AI in enhancing transparency and competition within the marketplace. Cortland’s initiative not only aids consumers in making informed choices but also encourages pub owners to remain competitive in their pricing.

Note: The information presented in this article is based on data available as of March 2026 and may be subject to change.