EVE trader's glossary

Short definitions of EVE Online market metrics and terms: margin, spread, fair value, turnover, ISK, PLEX, hubs and arbitrage.

Margin: Net profit per unit after all fees: (sell price − buy price − fees) ÷ buy price. The public “Margin” is computed on bare fees with no trade skills; “My margin” recomputes it from your real skills and standings.
Spread: The raw gap between the best sell and the best buy, as a percent of the mid price. It is the profit zone before fees — real margin is always narrower.
Fair value: The VWAP over history — the volume-weighted average price across the period from region-wide ESI history. High-volume days weigh more, so it is a stable anchor for the “normal” price rather than a snapshot of the order book.
Turnover: Average daily ISK turnover over 30 days — the primary liquidity measure. It answers the key question: will you be able to get out of a position.
Volume: Average daily trading volume in units. It shows how many units of the item actually change hands per day.
Volatility: The daily price spread (σ) in percent: the higher it is, the riskier the entry, because the price can move against you while your order sits.
Competition: The number of orders in a narrow band near the best price on each side (buy / sell). The more there are, the more often you will have to re-price.
Churn: How often the best order changes per hour — trading intensity. High churn means an aggressive fight for the front of the queue.
Refill: How many minutes the order-book depth takes to restock after it is eaten. Fast refill is good for liquidity, but it also means both demand and supply are brisk.
Spread persistence: The share of time the spread stays stably wide: whether the gap is real or just a one-off spike.
Days of inventory: How many days the current market depth lasts at the usual trade pace — an estimate of how long it will take to exit a position.
ISK: InterStellar Kredit — the in-game currency of EVE Online. All prices, profit and turnover in Mercator are denominated in it.
PLEX: EVE Online’s premium currency: an expensive, high-liquidity item with a thin percentage spread. It trades on a single universe-wide market, so there is no inter-hub arbitrage on it.
Skill injector: Packaged skill points: pulled with an extractor from characters with a large SP pool and sold to players who want to train faster. Big volume and predictable demand make it almost ideal for a turnover strategy; its price is tied to PLEX.
Trade hub: A major station that concentrates orders and turnover. Mercator covers five hubs: Jita IV — Moon 4, Amarr, Dodixie, Rens and Hek; each has its own volume, spread and competition level.
Station trading: Buying low and selling higher in one place without moving an inch: all the profit comes from the spread between buy and sell orders in the same hub, with no hauling.
Inter-hub arbitrage: Buying an item where it is cheaper, hauling it, and selling it where it is dearer. Profit = the price gap − both-side fees − the cost and risk of hauling; you are paid for cargo risk.
Instant vs Patient: Two selling modes. Instant — sell immediately into existing buy orders: fast, but lower margin because you cross the spread. Patient — place your own sell orders: higher margin, but slower and with the risk of being undercut.
Escrow: The ISK locked under a standing buy order until it fills or is cancelled. Escrow used to be reduced by the old Margin Trading skill, which was replaced by Advanced Broker Relations.
Broker fee: A fee for placing an order, on both buy and sell: about 3% at Broker Relations 0, ~1.5% at V, with a floor near 1% on good standings. Re-listing an order is charged at a discount (base 50%, up to 80% at Advanced Broker Relations V).
Sales tax: A fee charged when your sell order fills, on the sale price: about 7.5% at Accounting 0 (cut from 8% in a March 2025 patch) and ~3.4% at Accounting V. There is no tax on buying.
Break-even floor: The minimum spread at which a trade at least breaks even after all fees on both sides: roughly 14–15% on baseline skills and about 7% with trained Accounting and Broker Relations.