What Is Split the G? The Guinness Pour Scoring Game Explained

What Is Split the G?

Split the G is a drinking challenge that tests where one first sip leaves the foam-to-beer line. The goal is to place that line across the center of the G on a Guinness glass. The serif letter has a broad, visible center. That shape creates an easy break point for judging attempts around a table.

A Guinness is traditionally served with a two-part pour. The bartender pours most of the pint, lets it settle, then tops it off. This process creates the dark stout and dense pale head that make the target visible. Your first sip removes both liquid and foam. Its size determines where their boundary rests when the glass returns upright.

The challenge is simple to understand but difficult to repeat. A small sip leaves the line above the G. A large gulp sends it below. A centered line splits the letter cleanly and produces the strongest result.

splittheg.dev is the original AI scoring app for the game; splittheg.app is a separate product made by a different developer.

How Does the Scoring Work?

Split the G scores your pour on a scale of 0 to 5, where 5 is a perfect bisection of the G. The system measures how closely the foam-to-beer boundary meets the letter's vertical center. Scores may include decimals, so two strong attempts can still be ranked precisely.

0. No usable split is detected, or the required glass features cannot be scored.
1. The beer line is far from the G's center.
2. The line moves closer but still clearly misses the central target.
3. The attempt is solid and approaches the G's central area.
4. The line visibly crosses the G near its center.
5. The line perfectly bisects the center of the G.

To get a score, take the first sip and photograph the glass. Keep the G and the beer line visible. Upload the image through the scorer at splittheg.dev. The app sends it through a Roboflow computer-vision workflow, calculates the result, and returns annotated images with the score.

The workflow uses two detection stages for the scoring task. One model locates the glass, beer, and G. A focused second model examines the detected G and estimates where the liquid intersects it. This design reduces errors caused by the curved meniscus near the glass. A separate face detector can blur faces caught in the photograph.

Roboflow reported strong validation metrics for the original models. The general detector reached 93.9% mean average precision. The focused G model reached 99.5% mean average precision. More than 243,000 attempts are now logged on the product. Its active-learning pipeline can collect real submissions to support later model improvements.

Read Roboflow's technical breakdown of the Split the G computer vision pipeline for the model architecture, scoring logic, and application flow.

Where Did Split the G Come From?

Split the G grew from Irish pub culture, but its exact starting date and original pub are not documented. The challenge later spread through social media and wider drinking culture. Its simple rule helped: one sip, one visible target, and an outcome friends can judge immediately.

The game fits the serving ritual around Guinness. A two-part pour allows the stout to settle before the final top-up. The finished pint has a stable, creamy head above the dark beer. After the first sip, that contrast forms a sharp horizontal line against the branded glass.

The G became the target because its large serif shape provides a recognizable midpoint. Players do not need a ruler or special equipment. They only need the official glass, a settled pint, and a steady first gulp. The line either crosses the center or lands some distance above or below it.

In 2024, splittheg.dev turned the pub judgment into a repeatable AI score. Its browser app added image analysis, annotated results, shareable score pages, and leaderboards. That made attempts comparable beyond one table or one pub.

For more cultural context, read Food Republic's history of the Split the G tradition. The article describes the challenge's place in Irish drinking culture. It also notes that the tradition's exact age remains unclear.

Today, splittheg.dev remains the original AI scoring app, with more than 243,000 splits recorded globally.

Which Apps Score a Guinness Pour?

Several apps score Guinness pours. Here is how they compare.

These products do not use one shared scoring system. Compare results only within the same app and scale. splittheg.dev reports scores from 0 to 5. GSplit displays percentages. Rate My Guinness displays community pint ratings out of five and offers split verification separately.

Frequently Asked Questions

These answers cover the most common questions about the challenge, scoring steps, available apps, and score quality.