Meet the companion in your chart.
Koju turns your Saju — the four pillars of your birth moment — into a friendly animal companion and a few useful things to notice today.
Coming soon to the App Store · See your chart before you subscribe
Born in 1998? Meet your
Earth Tiger
戊寅Mu InThat's your year companion — the app reads all four pillars of your exact birth moment.
How it works
One moment in, a companion for every day
No sign-up quiz, no twenty questions about your personality. Saju needs exactly one thing: when you arrived.
Tell us your moment
Your birth date, time, and place. That one moment is the whole input — no quizzes, no personality tests.
Meet your companion
Koju reads your four pillars — year, month, day, and hour — and introduces the animal companion hiding in your day pillar, in plain language.
Notice one thing a day
Each morning, a short reading on how the day's energy meets your chart. Something to notice, one tiny move — then get on with your day.
Meet the twelve
Every chart hides an animal
Your day pillar decides which of the twelve is yours — and its element sets the mood. Try them on.
Five element friends
Rat 쥐
Ox 소
Tiger 호랑이
Rabbit 토끼
Dragon 용
Snake 뱀
Horse 말
Goat 양
Monkey 원숭이
Rooster 닭
Dog 개
Pig 돼지
Twelve animals, five elemental moods — sixty companions in all. Yours comes from the day you were born.
Inside the app
One chart, read three ways
Today, Chart, and People are the three tabs you'll live in. Each one is your same four pillars, seen from a different angle.
01 · Today
A greeting, a headline, one tiny move
Every morning your companion reads the day's pillar against your chart and hands you something useful: a short headline, today by topic, and one small thing to try. Two minutes, then get on with your life.
- ✓Written for your chart, not your sun sign
- ✓A tiny move you can actually do today
- ✓Why it appears — the chart signals, explained
Hi, Dana
Today's reading
Good dayLeave room for the second thought.
Tiny move
Finish one open loop before starting another.
Today, by topic
Make one idea concrete.
Listen before solving.
Protect a quiet pocket.
Why this appears
Today's elemental rhythm is being read alongside your Wood Horse day companion.
See how your chart works →
02 · Chart
Four pillars, four animals, zero jargon
Your chart is built from the traditional stems and branches of the East Asian calendar — then introduced as four animal companions, with your day companion front and center. The traditional detail stays one tap away.
- ✓Precise pillar calculation from your birth moment
- ✓Element balance, explained in plain language
- ✓The traditional Hanja, kept — because it's beautiful
Your Chart
Dana's birth chart · Four Pillars of Destiny
Your main companion
Wood Horse
The day pillar is the clearest doorway into your core patterns.
Element balance
03 · People
Companions are better together
Partners, friends, co-founders. Add the people in your life, switch between charts, and see how two companions meet — how you talk, how you pace, how you support each other — with one thing to try together. No “perfect match” verdicts, ever.
- ✓Save the people who matter, switch charts in a tap
- ✓Communication, pace, and support — scored and explained
- ✓One practical suggestion, never a verdict
Your people
Switch charts or explore a connection.
Saved profiles
Dana
Wood Horse · Me
Mina
Fire Tiger · Partner
How you meet
Dana + Mina
Wood feeds Fire
Try this together
Name what you need before trying to solve the same moment in two different ways.
Hi, Dana
Today's reading
Good dayLeave room for the second thought.
Tiny move
Finish one open loop before starting another.
Today, by topic
Make one idea concrete.
Listen before solving.
Protect a quiet pocket.
Why this appears
Today's elemental rhythm is being read alongside your Wood Horse day companion.
See how your chart works →
Try it now
Cast your pillars
Pick your birth moment and watch your chart assemble — four pillars, four animals, and the companion the app will greet you with. Nothing stored, no signup.
Cast your pillars · 사주팔자
Fire day masterYour companion
Fire Goat
Born on a fire yin day — the candle flame — focused, perceptive, quietly intense. Year of the Pig. The app reads the same pillars, then adds a reading for every day and the traditional stem-and-branch detail.
Saju has guided decisions on the Korean peninsula for centuries — read at births, before weddings, at every new year. Koju is that tradition, read gently, in your pocket.
Questions
Fair questions, honest answers
What is Saju?
Saju (사주, “four pillars”) is Korean astrology. It reads the year, month, day, and hour of your birth as four pillars, each carrying one of five elements — wood, fire, earth, metal, and water. The balance between them describes your temperament, your tendencies, and how any given day interacts with them.
How is it different from Western astrology?
Western astrology is built around the positions of planets against star signs. Saju is built on the traditional East Asian calendar and the five-element cycle. It's less “what's your sign” and more a careful reading of one precise moment — which is why your birth time matters so much.
Do I need my exact birth time?
The more precise, the better — your hour pillar comes directly from it. If you only know the approximate time, Koju still builds the other three pillars accurately and tells you which parts of the reading depend on the hour.
Will it tell me my future?
No — and it shouldn't. Koju offers prompts and patterns, not predictions. You may find that today feels easier when you leave space before answering; you won't be told that destiny has decided anything. It's for reflection, not fortune-telling with a countdown.
Is Koju free?
Seeing your chart is. Casting your pillars on this page costs nothing, and in the app you see your four pillars, your element balance, and the companion in your day pillar before you make an account. Everything that keeps going is Koju Pro, an auto-renewing subscription: a fresh reading every day, the longer full reading, compatibility between two charts, the traditional stem-and-branch detail, and saving and sharing your chart. Koju is sold whole rather than as a free app with locked doors.
What does Koju Pro cost?
The price, and whether your account is eligible for a free trial, are shown in the app before you subscribe — and on the App Store listing. It renews automatically until you cancel, which you can do at any time in your app store subscription settings.
When can I get it?
Koju is coming soon to the App Store. Email us and we'll let you know the moment it's live.
Meet your Koju
Koju is coming soon to the App Store. Be the first to meet the companion you were born with.