What a crypto arbitrage scanner does — and what to look for in one

A crypto arbitrage scanner does one job: it watches prices for the same asset across many exchanges at once and tells you where the gap is wide enough to be worth acting on. Doing that by hand is impossible — there are thousands of pairs, prices move in milliseconds, and the best windows tend to open when you are not looking.

At the core, a scanner measures two things. The first is spread: the price difference between two venues for the same asset, ideally calculated on the prices you could actually fill, not on stale last-trade numbers. The second is funding: the periodic payment between longs and shorts on perpetual futures, which decides whether holding a hedge costs you money or pays you.

The biggest design choice is coverage. Many tools scan a whitelist — a curated list of popular pairs — because it is simpler and keeps the screen tidy. The catch is that popular pairs are exactly where everyone is already looking, so gaps there close fast. The wide, short-lived gaps tend to live on the long tail of altcoins and new listings, which a whitelist never shows you.

Arbitrex takes the opposite approach: it covers every pair with no whitelist, across spot and perpetual markets on the exchanges it connects to, and shows spreads and funding live. That includes routes like Gate.io arbitrage and MEXC arbitrage, where thin long-tail books produce the gaps you will not find in a short curated list.

When you evaluate any scanner, ask a few direct questions. Is the spread net of fees or gross? Does it account for order book depth, or just top-of-book? How fresh is the data, and how long does it take a new gap to appear? Can you filter by exchange pair, spread size and funding? A scanner that answers these honestly saves you from the phantom spreads that look great and fill badly.

A scanner finds opportunities; it does not make them safe. You still need to check depth at your size, confirm deposits and withdrawals, and size positions so one failed leg does not hurt. Used that way — as a fast, wide filter that hands you a short list of routes worth a closer look — a crypto arbitrage scanner turns a full-time watching job into a few minutes of decisions.