Where the numbers come from and how often they refresh

Ten venues, a recount every second, and what "stale data" means.

Short answer

The numbers come straight from the exchanges over a standing connection — order books, prices, funding rates. Ten venues are connected today, with their spot, futures and margin markets.

The list of spreads is recomputed every second from the latest state of the books. The set of instruments — which pairs exist on the venues at all — is re-read every five minutes, so a new listing shows up within a few minutes of appearing.

When data counts as stale

A quote older than five minutes is not treated as live. A spread with a leg like that is not shown as current.

The connection itself is watched separately by an indicator in the spread's card: Feed live, Feed lagging, Feed down or Feed unknown. It asks two different questions — are we connected to the venue at all, and has this particular instrument updated — and shows the worse of the two answers. A green light over numbers nobody has refreshed is exactly the failure an indicator must not have.

Why a number can differ from the exchange

• Time passed. There are seconds between what you see and what is in your terminal.
• We read the top of the book. The price in the list is the best bid and ask, not the last trade.
• The venue's book has frozen. It happens, and those spreads are marked.

What about history

The spread and funding charts are built from our own measurements collected over time, not fetched from the exchange when you open the card. So a freshly listed instrument has a short history or none at all — that is not a fault.