Coming July 1, 2026
Your destiny, written 1,500 years ago. Decoded by AI.
Korean Saju (Four Pillars Method) — the science behind K-culture wisdom. Direct. Verifiable. Built by a 49-year-old Korean fullstack builder, in public for 5 years.
LAUNCHJuly 1, 2026·0 on the waitlist
50% lifetime discount for first 1,000·Free beta — 50 spots·Build in Public — every Sunday
§ 01 — What is Saju?
Not astrology. Older. Deeper.
A 1,500-year-old Korean system. Now decoded for you.
Western astrology has 12 zodiac signs. Korean Saju has 60 갑자 × 5 elements (Wood / Fire / Earth / Metal / Water) mapped across 4 pillars (year · month · day · hour). That's roughly 518,400 unique combinations vs astrology's 12.
Saju doesn't predict events. It maps the underlying energetic structure of your life — when to push, when to wait, who balances you, what cycle you're in. K-pop stars consult Saju masters before contracts. Korean parents check Saju before naming babies. It's not folklore — it's pattern recognition over millennia.
We trained AI on the actual Korean classics — 적천수 (Drops of Heaven), 궁통보감 (Mirror of Wealth and Suffering), 자평진전 (Ziping's True Lineage) — and made it speak in the direct, modern English you'd hear from a friend who happens to be a 1,500-year-old sage.
§ 02 — Why Mr. Ban Saju is different
Six things no one else does.
Not Co-Star. Not The Pattern. Not Korean apps.
01
Direct Tone — Eastern Depth
"Your Wood is too dry this year. Don't start anything in March. Wait for the May rain." — Co-Star's directness + Saju's precision.
02
Life Phase Navigator
Translates 대운 (10-year cycles) into modern English. "You're at the peak of Wood phase. Fire begins in May 2027."
03
RAG with Source Citations
Every reading cites the classical text it draws from. AI hallucinations meet 1,500-year-old verifiable wisdom.
04
Couple 5-Year Cycle
Not "compatible / incompatible." We map both your 5-year cycles together — when you rise, when you protect each other.
05
K-culture Discovery
BTS RM's Saju. Squid Game characters' Pillars. K-pop industry insider perspective — impossible for Western apps.
06
Built in Public for 5 Years
49-year-old Korean builder, 40 years of code, weekly numbers public until 2030. Your support funds a 5-year experiment.
§ 03 — vs Co-Star, The Pattern, Korean apps
Different system. Different builder.
| Axis | Co-Star | The Pattern | Mr. Ban Saju |
|---|
| System | Western astrology (12 signs) | Self-developed | Korean Saju (60갑자 × 5 elements × 4 pillars) |
| Tone | Direct, blunt | Analytical, soft | Direct + Eastern depth |
| Source | NASA + astrologers | Black box | Verified Korean classics with citations |
| K-culture aware | No | No | Native — by design |
| Couple analysis | Sign compatibility | Personality match | 5-year cycle map |
| Builder transparency | NYC startup | Startup | Solo builder, 5-year public experiment |
§ 04 — Two formats, one engine
Visual or deep — your choice.
We made two products from the same Saju engine, because not everyone reads the same way.
✨
Curious Mind
10s ~ 40s · Gen Z · Millennial
- SWOT visual matrix (career · money · love · health)
- 5-year timeline graphic
- Daily Card — Co-Star style, 30-second read
- Couple 5-year cycle chart
- K-culture Discovery (BTS · K-drama · K-pop)
- Instagram & TikTok shareable visuals
Free · Pro $9.99/mo · Premium $14.99/mo
📜
Deep Reader
40s+ · Senior · Saju practitioners
- 30+ page detailed PDF report
- Classical citations (적천수 · 궁통보감 · 자평진전)
- 10-year cycles broken into life domains
- Historical figure comparisons (same Day Master)
- Annual renewal updates
- For self · spouse · children · clients
$29 / report · Lifetime renewal $79
Saju Practitioners (B2B): White-label licensing for studios. Inquire on waitlist →
§ 05 — Why I'm building this
A 5-year public experiment.
FROM THE BUILDER
I'm 49. I've been writing code since I was 10.
I built this. I'll publish every number for 5 years.
I started coding at age 10 with GWBASIC in Korea. I've been a fullstack developer for 20 years. In 2024, I single-handedly delivered a ₩200M (~$150K) AI project. I run a corporate web agency since 2016 — so this 5-year experiment isn't about survival. It's about
proving a 49-year-old Korean builder can reach $1M/year by 2030, while publishing every number, every failure, every decision. Saju has been quietly shaping Korean culture for 1,500 years. AI now lets us share it with the world — not as folklore, but as the precise, beautiful pattern system it has always been.
You'll get every weekly update, every revenue number, every failure obituary. If we hit our target, you'll have been part of it. If we don't, you'll know exactly why.
Read the full story →§ 06 — FAQ
Common questions.
When does it launch?
Beta: June 16, 2026 (50 spots from waitlist). Public launch: July 1, 2026 on Product Hunt. Waitlist members get 24-hour early access and 50% lifetime discount.
Do I need to know my exact birth time?
For maximum accuracy yes — Saju uses Year · Month · Day · Hour pillars. If you don't know your birth hour, we provide a "Day Master only" reading that's still deeply useful (about 75% of full accuracy).
Is this real or just for fun?
Saju is a 1,500-year-old structured pattern system, not folk fortune-telling. It's used by Korean entertainment companies for casting, by parents for naming children, by Saju masters as professional consultants. Treat our app as a wisdom tool — for inspiration, perspective, and pattern recognition. Not medical, financial, or legal advice.
How is this different from Co-Star?
Co-Star uses Western astrology (12 zodiac signs). Mr. Ban Saju uses Korean Four Pillars (518,400+ combinations). Co-Star pushes daily mood. We map decade-long life cycles. Co-Star is built in NYC. We're built in Korea, by a Korean 49-year-old, in public for 5 years.
Is my data private?
Yes. We're GDPR + CCPA compliant. Your birth data is stored encrypted and never sold. You can export or delete everything anytime. We don't run ads — we're funded by subscriptions only.
Will there be a Korean version?
Yes — the original Korean version already exists at
atozai.kr. This English version brings the same engine to global K-culture fans, Korean diaspora, and the curious world.
§ 07 — Join the waitlist
Be among the first 1,000.
Get a 50% lifetime discount code on launch day. 50 of you will be invited to the free beta in mid-June. Weekly Builder's Note delivered to your inbox until launch.