Javanese Primbon (爪哇命書)

Weton & Pawukon — Reading a Birth-Date in the Javanese Almanac

Overview

Primbon is the living almanac of Java — a body of divinatory knowledge, gathered in manuscripts like the Serat Primbon and the Betaljemur Adammakna, that ordinary Javanese families still consult to name a child, choose a wedding day, or weigh a marriage. At its heart is the WETON: the moment of birth read not in one calendar but in two interlocking weeks running at once. The familiar seven-day week (Saptawara: Minggu through Sabtu) turns alongside an older five-day market week (Pasaran: Legi, Pahing, Pon, Wage, Kliwon), and the pair that fall together on your birthday — say 'Senin Pahing' — is your weton, repeating only once every thirty-five days. Each of those twelve days carries a number, the NEPTU, and the sum of your two neptu (a value from 7 to 18) is the key that unlocks the Primbon's character and fortune tables. Layered over this is the PAWUKON, a 210-day ritual calendar of thirty named weeks (wuku), each governed by a guardian deity with its own tree, bird, and temperament. askTIAN computes all of it from a single birth-date with exact calendar arithmetic — the weton and its neptu, the wuku and its deity, the Pancasuda and seven-fold character lots, and, given a partner's date, the famous Jodoh marriage-compatibility reckoning — and is candid that this is Javanese cultural divination, deterministic and symbolic, not prediction.

Origin & history

The Primbon tradition is the syncretic heart of Javanese metaphysics, where indigenous Austronesian day-counting, Hindu-Buddhist calendrics carried from India, and Islamic almanac lore settled into a single household science over many centuries. The five-day Pasaran is ancient and distinctively Southeast Asian — its days were the rotating market days of old Java. The 210-day Pawukon of thirty wuku is shared with Bali, where it still orders the temple calendar, and traces to the Hindu-Javanese courts; the Serat Pawukon manuscripts assign each wuku a story, a deity from the wayang pantheon (Bathara Guru, Wisnu, Brama, Sri, Durga and the rest), and a fortune. When Islam came to Java the material was absorbed into the Primbon almanacs — most famously the Betaljemur Adammakna compiled in the Surakarta keraton — which fused the day-counts with numerology, the lunar Hijri months, and Sufi cosmology. The result is neither purely Hindu nor purely Islamic but specifically Javanese (Kejawèn), and it remains in daily use across Central and East Java today.

askTIAN is precise about what is firm in this tradition and what varies between manuscripts. The NEPTU values are the bedrock and are unanimous across every reputable source — Saptawara: Minggu 5, Senin 4, Selasa 3, Rabu 7, Kamis 8, Jumat 6, Sabtu 9; Pasaran: Legi 5, Pahing 9, Pon 7, Wage 4, Kliwon 8 — so a weton's neptu (7–18) is fixed. (A widely-copied online table that swaps Minggu and Rabu is a transcription error; askTIAN does not use it.) The character lots are pure modular tables on the neptu: the five-fold PANCASUDA (Sri, Lungguh, Gedhong, Lara, Pati) and a seven-fold watak ladder (Wasesa Segara through Lebu Katiup Angin). For marriage the JODOH reckoning sums both partners' neptu modulo eight to one of eight named outcomes (Pegat, Ratu, Jodoh, Topo, Tinari, Padu, Sujanan, Pesthi); a competing base-nine fold appears in some manuscripts, which askTIAN documents but does not use, following the mod-8 rule that matches the most widely published worked examples. The Pawukon's symbolic lore — which deity, tree, and bird belongs to each wuku, and the temperament read from it — genuinely differs between pesantren and keraton copies, so askTIAN treats that layer as traditional lore rather than fixed doctrine, while the calendar position itself is exact.

How it works

Everything follows from the birth-date by deterministic calendar math — no randomness and no ephemeris. askTIAN converts the date to a Julian Day Number and from it reads both weeks at once: the Saptawara day (JDN+1 mod 7) and the Pasaran day (JDN mod 5) give the weton and, by adding their neptu, the neptu total. The same JDN places the date in the Pawukon by the standard epoch formula — position = (JDN − 146) mod 210 — which fixes the wuku (one of thirty), the day within that wuku (1–7), and the day-of-cycle (1–210). Because 210 divides evenly by five, the great Balinese holy days fall straight out of this arithmetic and serve as the engine's hardest accuracy locks: Galungan is always Buda Kliwon of wuku Dungulan (Pawukon day 74) and Kuningan always Saniscara Kliwon of wuku Kuningan (day 84) — askTIAN reproduces both to the day (e.g. Galungan on 2025-04-23, Kuningan on 2025-05-03), alongside eleven gold weton vectors such as Kartini's birth (1879-04-21 → Senin Pahing, neptu 13) and the 1945 Proclamation (1945-08-17 → Jumat Legi, neptu 11). From the neptu the engine derives the Pancasuda and seven-fold character lots; the wuku contributes its guardian deity and temperament. Supply a partner's birth-date and the engine computes their weton too and runs the Jodoh table on the combined neptu, returning the named outcome with a symbolic harmony emphasis. The response is structured throughout, with an optional best-effort LLM reading in five parsable sections and explicit honesty rails.

Good for

Use cases

Weton & Neptu

Send a birth-date and get the weton (e.g. 'Senin Pahing'), each day's neptu and Javanese name, the neptu total, and the 35-day selapan cycle — a deterministic spine for a Javanese birthday or character feature, no LLM required.

Pawukon Placement

The response places the date in the 210-day cycle: the wuku with its guardian deity, tree, bird and temperament, the day within the wuku, the day-of-cycle, and a flag when the date is a Balinese holy day (Galungan, Kuningan, Saraswati, Pagerwesi).

Character Lots

From the neptu the engine returns the five-fold Pancasuda and seven-fold watak categories with their traditional meanings — a compact, deterministic character reading that pairs naturally with the wuku's temperament.

Jodoh Compatibility

Add a partner's birth-date and the engine runs the Petung marriage table on the combined neptu, returning the named outcome (Ratu, Jodoh, Pesthi, Pegat …), its meaning, and a symbolic 0–100 harmony emphasis — distinct from the astrological synastry endpoints.

Key terms

Weton
A person's birth-day read as the pairing of the seven-day Saptawara (Minggu…Sabtu) and the five-day Pasaran (Legi, Pahing, Pon, Wage, Kliwon) — e.g. 'Senin Pahing'. The pair repeats every 35 days, a cycle called the selapan.
Neptu
The numeric value of a day. Each Saptawara and Pasaran day has one (Saptawara 3–9, Pasaran 4–9); a person's neptu is the sum of their two, ranging 7–18. It is the key that drives the Primbon's character, fortune, and compatibility tables.
Pawukon & Wuku
The 210-day ritual calendar of thirty named weeks. Each week is a wuku (Sinta, Landep, … Watugunung) of seven days, governed by a guardian deity with its own tree, bird, and temperament. A date's wuku and day-of-cycle are fixed by the epoch formula (JDN − 146) mod 210.
Pancasuda
The five-fold character lot read from the neptu ((neptu−1) mod 5 + 1): Sri (prosperity), Lungguh (dignity), Gedhong (wealth/storehouse), Lara (hardship), Pati (endings). A compact temperament-and-fortune classification.
Seven-fold watak
A second character ladder from the neptu ((neptu−1) mod 7 + 1): Wasesa Segara (ocean-wide), Tunggak Semi (ever-sprouting), Satria Wibawa (authority), Sumur Sinaba (the well drawn from), Satria Wirang (the shamed knight), Bumi Kapetak (buried earth), Lebu Katiup Angin (dust on the wind).
Jodoh (Petung Salaki-Rabi)
The marriage-compatibility reckoning: the two partners' neptu summed modulo eight to one of eight outcomes — Pegat, Ratu, Jodoh, Topo, Tinari, Padu, Sujanan, Pesthi — each describing the character and prospects of the union.
Selapan
The 35-day cycle on which a weton recurs (the least common multiple of the 7-day and 5-day weeks). Selapanan is also the Javanese 35-day celebration held for a newborn, marking the return of its weton.

API

The askTIAN Javanese Primbon API reads a birth-date in the Serat Primbon and Serat Pawukon tradition using exact calendar arithmetic — no ephemeris, fully deterministic. From one date it returns the WETON (the Saptawara × Pasaran pairing with each day's neptu and Javanese name, the neptu total, and the 35-day selapan), the PAWUKON placement (the wuku with its guardian deity, tree, bird and temperament, the day-of-cycle, and any Balinese holy day it coincides with), the PANCASUDA and seven-fold watak character lots derived from the neptu, and a character summary. Supply a partner's birth-date and it adds the JODOH (Petung) marriage-compatibility reading — the combined neptu taken modulo eight to one of the eight named outcomes, with a symbolic harmony emphasis. Accuracy is the priority: the engine is locked by unit test against the Balinese holy-day anchors that fall straight out of the Pawukon epoch (Galungan = day 74, Kuningan = day 84, verified on real 2025 dates), eleven gold weton vectors (Kartini, the 1945 Proclamation, and more), and the 35-day weton / 210-day Pawukon cycle invariants. It is honest about its sources: the neptu tables are unanimous (transposed variants are rejected), the Pancasuda and seven-fold lots are pure modular tables, Jodoh uses the mod-8 rule (the base-9 variant is documented, not used), the Pawukon symbolic lore is manuscript-variable, and the whole reading is symbolic cultural divination, not prediction — and not medical, legal, or financial advice. A best-effort LLM reading is returned in five parsable sections; set interpretation:false for structured data only.

Endpoint: POST /trpc/primbon.compute — 6 TIAN Points. See the API documentation and Playground.