Who it's for — Anyone who looks at an asset's price and doesn't understand why, if they decide to buy right now, they will pay a slightly higher figure than the one shown on the chart. The spread reveals the hidden mechanics of the market.
In trading, there is never just a single price. At any given moment, there are two competing prices:
- Bid: The highest price a buyer is willing to pay.
- Ask: The lowest price at which a seller is willing to sell the asset.
The Bid-Ask Spread is the distance (the void) between these two prices.
In simple terms — Imagine selling a used car. You ask for $10,000 (Ask), the best buyer offers you $9,500 (Bid). That $500 difference is the spread. Until one of the two gives in (accepting the other's price), the trade does not happen.
The mechanics of the void
The spread is literally an empty space in the Order Book. It is the zone where, in that precise millisecond, there are no buyers or sellers willing to negotiate.
When this space is small (e.g., EUR/USD often has a spread of 0.0001), the market is said to be liquid and efficient: buyers and sellers are extremely close to finding an agreement. When this space is huge (e.g., an obscure cryptocurrency at 3 AM), the market is illiquid: the distance between buyer and seller is vast.
| Instrument / Time | Type of Spread | Meaning |
|---|---|---|
| Apple Stock, EUR/USD | Tight | High competition, easy to enter and exit. |
| Altcoins, Penny Stocks | Wide | Low participation, "thin" market. |
| During Breaking News | Widening | Market Makers pull orders to protect against volatility. |
The role of Market Makers
In many markets, the spread is not only created by retail traders failing to agree, but is managed by Market Makers. These entities always position themselves on both the Bid and the Ask. Their job is to guarantee that you can always buy and sell. Their "reward" for providing this service is the width of the spread itself: they buy from you at 99 and sell to someone else at 101, pocketing the difference.
Summary Sheet
- What it is: The algebraic difference between the best Ask and the best Bid (Ask - Bid).
- What it's for: It measures the efficiency and liquidity of a market at a given moment.
- The key concept: Don't confuse the Spread (the distance between orders on the book) with the Price (the last executed trade).
Bronze Path — Module 1: What is a market. Next lesson: The Spread as a cost. Return to index: bronze-path.
Links
- price — The last agreement made across the spread.
- spread-cost — The economic impact of the spread on your pockets.
- liquidity — What causes the spread to widen or tighten.
- order-book — Where the Bid and Ask orders reside.
- bronze-path
- concepts
Module: Module 1 — What is a market
Understand that the market is not a line going up and down, but a place where exchange happens.
