What does going long or short mean?
Going long means buying so that you gain if the price rises and lose if it falls. Going short is the mirror: you sell first, gain if the price falls and lose if it rises. Either way the result is the price move times your size. On a perpetual, a short is the other side of the contract, so it needs no coin.
- A long gains when the price rises and loses when it falls. A short is the mirror image.
- Either way the result is the price move times the size: 10 units and a move of 5 is $50, gained or lost.
- On a perpetual, long and short are the two sides of one contract, so a short needs no coin to borrow or hold.
- Adding to a position moves its entry price to the size-weighted average. Closing part of it leaves the entry where it was.
- Hyperliquid’s closed PnL includes the fee, so a trade that only opens or adds shows its fee alone.
Long and short
To go long is to buy: you gain if the price rises and lose if it falls. To go short is the mirror image: you sell first and buy back later, so you gain if the price falls and lose if it rises.
The words describe a position, not a forecast. With 10 units at 100, every point the price moves is $10. Long, a rise to 105 is +$50 and a fall to 95 is −$50. Short, the same two moves are −$50 and +$50.
How a short works on a perpetual
A perpetual future is a contract on the price, not the coin. Every position has a buyer on one side and a seller on the other, so opening a short is selling the contract: no coin is borrowed and none needs to be held. What a perpetual future is covers the contract itself.
Because both sides hold the same contract, a long and a short of the same size from the same price have mirror results, before fees and funding. How funding works covers the payment that passes between the two sides while positions are open.
The entry price, when you add
Hyperliquid works out a position’s entry price as the size-weighted average of the current entry and the price of each trade that adds to it. Buy 10 at 100 and 10 more at 96, and the entry of the 20 is 98.
A trade that closes part of the position leaves the entry where it was. Sell 10 of those 20 at 99, and the 10 that remain still have an entry of 98.
Unrealised and closed PnL
While a position is open, its unrealised PnL is the side times the mark price minus the entry, times the size, where the side is 1 for a long and −1 for a short. A long of 10 with an entry of 98 and a mark of 100 shows +$20. Mark price and oracle price explains the price used.
When a trade closes part or all of a position, its closed PnL is booked. Hyperliquid’s closed PnL includes the trading fee, so a trade that only opens or adds shows a closed PnL equal to its fee: a small loss before the price has moved.
On Hyperliquid
On spot, Hyperliquid counts a buy as an opening trade and a sell as a closing one, so the same entry and closed PnL rules apply to coins you hold. That is why spot markets are described in buys and sells rather than longs and shorts.
In BuildTrade™, the order ticket shows Long or Short on a perpetual and Buy or Sell on spot. The Positions tab shows each position’s size, entry, mark and unrealised profit and loss, and Trade History shows every fill with its fee and realised result.
One long, four trades
Example numbersA long built in two buys and closed in two sells, worked out with Hyperliquid’s rules for the entry price and the closed PnL. Fees are left out of the table and counted in the note.
- Units bought in total
- 20
- Entry after both buys
- 98.00
- Closed PnL before fees
- +$40
| Trade, units | Price | Position after | Entry price | Closed PnL |
|---|---|---|---|---|
| +10 | 100.00 | 10 | 100.00 | $0 |
| +10 | 96.00 | 20 | 98.00 | $0 |
| −10 | 99.00 | 10 | 98.00 | +$10 |
| −10 | 101.00 | 0 | — | +$30 |
Taker fees at 0.045% on the $3,960 traded come to $1.78. Hyperliquid’s closed PnL includes each trade’s fee, so the two buys would show their fee alone, as a small negative number.
Mistakes that cost traders money
- Thinking a short needs the coin.
On a perpetual, a short is the selling side of a contract. Nothing is borrowed and no coin is held.
- Forgetting a short has no price ceiling.
A long loses at most what a fall to zero costs. A short loses more the higher the price goes; a stop and the liquidation price are what end it.
- Adding to a loser without reading the new size.
Adding lowers a long’s entry, but the position is larger, so every point against it now costs more.
- Expecting a partial close to move the entry.
Closing part of a position books a closed PnL and leaves the entry where it was.
- Leaving fees out of the result.
Hyperliquid’s closed PnL includes the fee, so even the opening trades show a small loss.
Try it in BuildTrade™
Switch the top bar to PAPER, open a small long, and watch the Positions tab: the unrealised profit and loss moves with the mark price, the size times each point.
Fee · Funding · Liquidation · Mark price · Unrealised P&L
Entry price and pnl, Hyperliquid Docs (read October 20, 2026).
Fees, Hyperliquid Docs (read October 20, 2026).
BuildTrade™ is independent of, and not endorsed by, Hyperliquid.