Nhật Nguyệt: a Vietnamese lunar calendar and customs guide with cited sources

Vietnamese customs and beliefs are scattered: in older relatives' memory, in classical books few can read, and online in copied pages with no sources. That gap gets exploited. Families pay for rituals and charms they cannot check.

Nhật Nguyệt builds the knowledge first:

- 1,710 articles in Vietnamese, English and Chinese, citing classical texts and licensed press line by line, each claim labelled as calendar fact, recorded custom or folk belief

- A lunar calendar computed in Vietnam time and tested against NASA and Paris Observatory data

- Family reminders for death anniversaries, with a shared plan for who prepares what

- An AI assistant that answers only from our cited articles

- 33 open datasets under CC BY 4.0 with a DOI

It is on the web, iPhone and Android. Core features are free, with no ads.

I'd value your feedback, especially on two questions:

1. Is it clear what this is within a few seconds?

2. What would make you trust an app about culture and traditions?

https://nhatnguyet.org/en