Akhmad Erlangga
Founder of SPYLL
Akhmad Erlangga built SPYLL and runs its BaZi engine, the free calculators on this site and the journal. Every journal article is published under his name.
What he does at SPYLL
- Builds the engine that turns a birth date and time into four pillars, luck pillars and branch relations, shared by the free calculators and the paid report.
- Picks journal topics, checks each BaZi fact in an article against the engine tables, and publishes it.
- Sets the Chemistry rules, the two-chart compatibility reading, from the classical texts listed on the methodology page.
How SPYLL's calculations are checked
The SPYLL engine is tested against other calculators and against charts from classical texts, and the results are written down as they are, including where it falls short.
Four pillars: 10 of 10 correct
Ten test dates against china95.net (27 October 2026). Nine matched exactly; the tenth differed because china95 placed the 1995 立秋 at the wrong time, while VSOP87 and the Astronomical Almanac tables gave the same time SPYLL uses.
Against Master Sean Chan's calculator: 9 of 10 identical
The one difference was a birth at 23:30. SPYLL turns the day at 23:00 as the 子平 school does, that calculator waits for midnight, and both conventions are recognised.
Day Master strength: not as exact as the pillars yet
Against 327 charts from 滴天髓闡微, 子平真诠 and 穷通宝鉴, the strong or weak direction matched on 65% of the held-out charts. That is why SPYLL names a single useful element only when two methods agree on a clearly read chart.
Weton: 13 of 13 matched
Weton from the SPYLL calculator matched the weton that 13 people wrote themselves in comments, next to their birth dates.
Sources
- 滴天髓闡微 (任铁樵 commentary), 子平真诠, 穷通宝鉴 and 三命通會 for reading rules and branch relations
- lunar-typescript for Li Chun and the 24 solar terms, cross-checked against VSOP87
- primbon.com for the weton compatibility count
Contact
Spotted a fact you think is wrong? Send it to [email protected] and we will check it against the engine.
Last updated: 2026-11-05