One Piece TCG · Market intelligence
Most One Piece cards fell. Our buy list finished higher.
Grand Line Ledger is a market tracker for the One Piece trading card game. That headline is our in-house signal engine at work: formulas we built ourselves and proved against 2.5 years of real recorded prices before a single call went live. Our buy calls finished higher 8 weeks later three times out of four, with our strongest tier above 80%, in a market where the typical card lost money. And we keep sharpening it: the engine is re-tested against the growing dataset every month. Don't take our word for it: every call is logged publicly the day it fires and graded automatically. We can't edit it, and you can check it right now.
1,128 verdicts fired on today's board. Free Google sign-in, takes 10 seconds. No card, no trial clock. The track record is public either way.
The record
Numbers we're proud to sign
In-house formulas. 2.5 years of real prices. Re-tested every month. The recipe stays in the vault; the results never do.
Backtested against 2.5 years of real recorded prices, every flag counted: winners and losers. The typical High Conviction call never traded below its flag price at all. Past results never guarantee the future, so the live ledger grades every new call in public. Observations, not financial advice; the ledger exists so you can judge them.
Every card gets a stamp. Every stamp gets a reason.
No jargon and no black box. Open any card and read exactly why it carries the verdict it does, in plain English.
An established climb still in motion, qualified against the version of the pattern our testing says actually pays: premium strength, or cheaper cards with room to run below their peak.
Falling hard, or a big run rolling over. Historically these kept falling more often than not. If selling was on your mind, this is the flag.
eBay listings drying up while the trend holds and the price hasn't spiked yet. Rare, and the classic setup before a move.
Washed out and just turning upward with the panic cooling. Speculative by design: small positions, eyes open.
Everything else gets HOLD: no signal worth acting on, and we say so rather than inventing one.
Live from today's board: the biggest swing
Monkey D. Luffy
This is the board working in real time: price history, eBay floor, PSA population, and the rule log explaining the stamp, all one click deep.
See the full breakdown →Built for how collectors actually play it
The full catalog
Every set, promo, pack, tin, and gift box. Singles and sealed, English and Japanese populations, updated daily.
The Radar
A daily mispricing scan: below-market eBay floors, grading plays where PSA 10 prices dwarf raw prices, and demand divergences.
Your portfolio, briefed
Track your collection and get plain-English readings on what you hold: what's running, what's rolling over, and what to do about it.
Signals tuned to you
Flipper, sealed investor, grader, or pure collector. Tell us once and the board reorders itself around how you play.
AUD & USD native
Prices, charts, and analyst notes in your currency. Built in Australia, fluent in both markets.
A public track record
The Signal Ledger logs every call the day it fires and grades it automatically at 4 and 8 weeks. We can't edit it. That's the point.
From the ledger desk
All articles →
One Card, Two Otamas: Best Selection Vol. 6 Craters While OP07 Keeps Climbing
The same character just had two completely different weeks — one printing of Otama is down more than half its value, while another is up 126% and still just a HOLD.
Jul 22, 2026
Otama and Perona Headline a Wano Rally the System Still Won't Chase
Two Wano alt-arts are up triple digits this month, but neither one earned an ACCUMULATE stamp — here's why the system is treating the week's hottest names with a raised eyebrow.
Jul 21, 2026
Roger's Manga Rare Nears Five Figures While the System Says "Wait" on the Week's Biggest Gainer
A vintage Gol D. Roger manga rare pushed toward eight grand overnight, but the single biggest percentage mover of the day — Otama — still can't shake its HOLD tag.
Jul 19, 2026The market moves every morning. So do we.
Fresh prices, supply counts, and populations before breakfast. New stamps on the board every day, and a strategy that re-tests itself every month. One free sign-in puts the whole deck in your hands:
The data play is the foundation. The toolkit is the reason you'll open it every day.
Get on the board freeFree Google sign-in, takes 10 seconds. No card, no trial clock. See pricing