01
Every observation keeps its source
A displayed price comes from a stored record with the provider, original currency, observed time, and a source link. We store the original value unchanged; any conversion is labelled with its rate and date.
Trust, in plain language
A price should show its work.
Collectors deserve evidence, not a confident-looking guess. Binder keeps every observation tied to its source, currency, time, and exact card printing. Browse exact card records02
No evidence means no price
If an approved source has not reported that exact printing and condition, Binder says no data. It never multiplies another marketplace value or substitutes a regional estimate.
03
Comparison stays like-for-like
Variant, finish, stamp, condition, grader, and grade stay attached to each observation. A future consensus will be published only when multiple eligible rows and stored exchange rates support it, with the method and timestamp visible.
04
Converted prices show their rate
When you choose a display currency, Binder converts with European Central Bank (ECB) reference rates, fetched daily from Frankfurter and stored. A price uses the latest stored rate on or before the day it was observed, never more than 7 days earlier; cross rates are calculated only from the same provider and date. The original amount and currency, the rate, and the rate date appear beside every converted figure. When no stored rate applies, the original amount is shown with a note saying so.
05
Your collection is not the price feed
Purchase cost, private notes, and collection details remain private to your account. Your data is not turned into a public market price, and CSV or JSON export remains free.