“I'm Javanese. Nobody builds a proper Weton reading in English. This did, and got the Neptu right.”
Weton
What’s your Weton?
Long before zodiac signs and personality tests, Javanese tradition had its own way of reading the day you were born. It is called Weton, the seven-day week paired with the ancient five-day Pasaran cycle: Legi, Pahing, Pon, Wage and Kliwon, making 35 unique birth-day combinations. Your Weton and its Neptu number are used in Primbon Jawa to explore character, relationships and fortune.
No birth time needed: we count the civil day. Primbon traditionally starts the day at sunset, so an evening birth takes the next day’s weton under that rule.
What is Weton?
Weton comes from the traditional Javanese calendar, in which every day belongs to two cycles at once: the familiar seven-day week, and the five-day Pasaran cycle, Legi, Pahing, Pon, Wage, Kliwon. Together they produce 35 possible Weton combinations, repeating every 35 days.
Each weekday and each Pasaran is assigned a traditional number: the Neptu, and adding the two gives your Weton’s Neptu. For example: Jumat = 6, Kliwon = 8, so the Neptu is 14. In Primbon, Neptu is then used for compatibility, auspicious dates and other forms of divination.
Weekday Neptu
Minggu 5 · Senin 4 · Selasa 3 · Rabu 7 · Kamis 8 · Jumat 6 · Sabtu 9
Pasaran Neptu
Legi 5 · Pahing 9 · Pon 7 · Wage 4 · Kliwon 8
The five Pasaran
The Pasaran is the older of the two cycles and the part with no Western equivalent. It ran as a market week: each of the five days was the day a particular market opened, so the cycle organised trade before it organised divination. In Primbon each carries both a Neptu and a character.
| Pasaran | Neptu | Traditionally read as |
|---|---|---|
| Legi | 5 | gentle and welcoming, an even temper, a knack for putting others at ease, and a quiet patience. |
| Pahing | 9 | strong-willed and ambitious. A person who wants much and pushes for it, generous but not easily moved. |
| Pon | 7 | bright and sociable: quick to speak, fond of company, and remembered for a certain sparkle. |
| Wage | 4 | steady and principled: firm, sometimes stubborn, dependable once committed. |
| Kliwon | 8 | perceptive and inward. Sensitive to what goes unsaid, and in folklore the pasaran most linked to the unseen. |
The seven weekdays
The weekday names come from Arabic by way of Islam’s arrival in Java, so Jumat (Friday) and Senin (Monday) will look familiar to anyone who knows the Arabic week. The Neptu attached to them, though, is Javanese.
| Day | English | Neptu | Traditionally read as |
|---|---|---|---|
| Minggu | Sunday | 5 | warmth and a wish to be seen, with a generous, open manner |
| Senin | Monday | 4 | care and diligence, a gentle steadiness that others lean on |
| Selasa | Tuesday | 3 | drive and directness, quick to act and slow to back down |
| Rabu | Wednesday | 7 | thoughtfulness and adaptability, a talker who reads a room |
| Kamis | Thursday | 8 | seriousness and depth, a long memory and a strong sense of duty |
| Jumat | Friday | 6 | grace and intuition, calm on the surface and watchful beneath |
| Sabtu | Saturday | 9 | energy and resolve, hard-working and protective of their own |
The highest Neptu a Weton can reach is 18, Sabtu Pahing, 9 and 9, and the lowest is 7, Selasa Wage. Neither is better; a high total is read in Primbon as a larger presence with more asked of it, not a stronger fate.
What the Neptu is used for
A Neptu on its own says little. It is an input, and Primbon puts it to three main uses.
Jodoh · compatibility
Two Neptu are added and the total read against an eight-part cycle: Pesthi, Pegatan, Ratu, Jodoh, Topo, Tinari, Padu, Sujanan. It is still consulted before Javanese weddings, sometimes seriously and sometimes as a formality.
Choosing a day
Neptu is used to pick dates for weddings, moving house, opening a business or beginning a journey, the same office the Chinese almanac performs.
Weton-day observance
Your Weton returns every 35 days. That period has its own name, selapan, and some families mark it with a small offering or a fast: a personal anniversary running on its own cycle rather than the year’s.
AsterNym computes the Weton and its Neptu exactly, and reports the Primbon reading as tradition. It does not tell you whom to marry or when to move.
What this calculation assumes
The five-day cycle has no astronomical event behind it. It is a count that has run without a break for centuries, so every date you can compute depends on knowing one date for certain. Here is the one we use, and the other choices that could move your answer.
- Pasaran anchor
- 17 August 1945, the Proclamation of Independence, is Jumat Legi. Every other date counts forward or back from it. You can check the anchor yourself: that day was a Friday, and it is the date most Indonesians know without looking it up.
- Day boundary
- We count the civil day, midnight to midnight. Primbon traditionally starts the Javanese day at sunset, so under that rule a birth after magrib belongs to the next day's weton. If you were born in the evening, your weton under the sunset rule is the following day's, which changes the pasaran, the neptu and therefore the jodoh reading. Both conventions are in live use; we count the civil day because that is the date on your documents, and we would rather tell you the rule exists than let you find out from a relative.
- Neptu values
- The standard Primbon numbers: Minggu 5, Senin 4, Selasa 3, Rabu 7, Kamis 8, Jumat 6, Sabtu 9, and Legi 5, Pahing 9, Pon 7, Wage 4, Kliwon 8. Your neptu is the two added, so it runs from 7 to 18.
- Not computed
- The 210-day wuku (pawukon) cycle, which is a separate Javanese-Balinese calendar with its own thirty weeks and its own readings. It is not part of a weton and this page does not attempt it.
Is Weton astrology?
Not exactly. Weton does not calculate the positions of planets or stars. It belongs to a different Javanese divination tradition, usually associated with Primbon Jawa. But it asks many of the same questions humans have asked through astrology, BaZi and numerology for centuries: who am I, who am I compatible with, and was there something meaningful about the moment I was born?
AsterNym explores these systems as cultural and metaphysical traditions, not scientific predictions.