The Common Experience

You open one almanac app. It says today is auspicious. You open another. It says today is inauspicious. A third gives it three out of five stars. All three claim to follow the Chinese almanac tradition. None of them agree.

This is not a minor inconsistency. If the methods were grounded in the same source texts, the results would converge. The fact that they diverge tells you something important: most almanac apps are not working from the same foundation. Many are not working from classical source texts at all.

What Most Apps Actually Do

The majority of almanac apps use simplified scoring systems. They take the day's stems and branches, run them through a reduced set of rules, and produce a single rating: good day, bad day, mediocre day. Some use color coding. Some use star ratings. The logic behind the score is usually opaque.

The problem with generic day ratings is fundamental. The classical Chinese almanac system was never designed to rate days generically. It was designed to evaluate specific activities on specific days. A day might be excellent for signing contracts but poor for travel. It might be favorable for medical treatment but unfavorable for groundbreaking ceremonies. Collapsing this into a single score discards the system's actual structure.

Different apps use different simplified rules. Some weight certain factors more heavily. Some include rules from regional folk traditions. Some appear to use algorithms that have no clear classical basis. The result: disagreement.

The Classical Approach

The authoritative text for Chinese almanac calculation is the Xieji Bianfang Shu (協紀辨方書), a 36-volume compilation commissioned by Emperor Qianlong and completed in 1739. This is not one person's opinion. It was compiled by court scholars including Prince Yunlu (允祿), Mei Gu (梅榖), and He Guozong (何國宗) to standardize conflicting almanac traditions that had accumulated over centuries.

The Xieji Bianfang Shu evaluates days by activity. Each activity has its own set of applicable rules drawn from the day's Heavenly Stem, Earthly Branch, lunar mansion, solar term, and various derived factors. The text provides transparent reasoning. You can trace exactly why a particular activity is rated auspicious or inauspicious on a given day.

Critically, the Xieji Bianfang Shu's design precludes generic day ratings. Its final volume explicitly rejects numerous folk simplifications, and the system's entire structure is built for per-activity assessment. The compilers understood that reducing a complex multi-factor evaluation to a single score produces unreliable results. The system was built for activity-specific assessment. Using it for anything else misrepresents the tradition.

Activity-Specific Evaluation

The classical system uses the terms yi (宜) and ji (忌), meaning "suitable" and "to be avoided." These are always attached to specific activities: suitable for marriage ceremonies, to be avoided for moving house, suitable for planting, to be avoided for litigation.

The evaluation considers multiple overlapping factors. A day's Earthly Branch might form a favorable combination for construction-related activities while simultaneously forming an unfavorable clash for travel. This is not a contradiction. It is the system working as designed. Different activities respond to different celestial configurations.

When an app shows you a single score for the day, it has already made editorial choices about which factors matter and how to weight them. Those choices are usually invisible to the user. The classical approach makes the reasoning visible.

How Six Lines Handles This

Six Lines follows the Xieji Bianfang Shu methodology. The almanac evaluates each day per-activity, showing which activities are favorable and which are not. The reasoning references the classical factors at work on that day. There is no single day score.

This is not a design choice made for novelty. It is the honest implementation of the source text. The Xieji Bianfang Shu was compiled precisely to resolve the kind of disagreements you see between modern apps. Following it means respecting the scholarship that produced it.

If three apps give you three different answers, the question to ask is not "Which app is right?" The question is: "Which app can show me why it reached its conclusion, and does that reasoning trace back to a classical source?" Transparency is the difference between a reference tool and a guess.