> For the complete documentation index, see [llms.txt](https://doc.pairex.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://doc.pairex.io/help/faq.md).
# FAQ
1. [**What chains are compatible with PairEx trading?**](/help/faq.md)
2. #### [**Can I be assured that my funds are secure and protected while using PairEx?**](#2-can-i-be-assured-that-my-funds-are-secure-and-protected-while-using-pairex)
3. #### [**How can PairEX assure zero slippage and spread while placing order?**](#3-how-can-pairex-assure-zero-slippage-and-spread-while-placing-order)
4. [**Are there any restrictions on opening positions?**](#3-how-can-pairex-assure-zero-slippage-and-spread-while-placing-order)
5. #### [**How is the remaining money handled after a liquidation?**](#5-how-is-the-remaining-money-handled-after-a-liquidation)
6. #### [**Is the security of smart contracts guaranteed?**](#6-is-the-security-of-smart-contracts-guaranteed)
7. #### [**How is the Net PnL of the position calculated?**](#7-how-is-the-net-pnl-of-the-position-calculated)
**1、What chains are compatible with PairEx trading?**
PairEx currently supports only Arbitrum, but plans to expand to other chains in the future.
#### **2、Can I be assured that my funds are secure and protected while using PairEx?**
As a decentralized exchange, PairEx does not require you to deposit or withdraw your assets from a centralized custody solution. Instead, your assets are always kept in your own wallet and under your own control, ensuring the highest level of safety and security for your funds.
#### 3、**How can PairEX assure zero slippage and spread while placing order?**
We operates as peer-to-pool trading model, where all quotes are derived from Chainlink oracle quotes and place order directly. This eliminates the spread on long and short prices, providing a fair and transparent trading environment. Additionally, we ensure sufficient depth in mainstream digital currency contracts to meet zero slippage due to the liquidity of trading currencies.
**4、Are there any restrictions on opening positions?**
| Pair | minimum limit(Opensize) | maximum limit(Opensize) |
|---|
| BTC_USDT | 500 USDT | 500,000 USDT |
| ETH_USDT | 500 USDT | 500,000 USDT |
#### 5、**How is the remaining money handled after a liquidation**?
In the event that there is leftover collateral following a liquidation event, it will be added back to the platform's vault, and utilized to offset the losses incurred from the liquidation. This means that after a position has been liquidated, the remaining collateral amount will be reduced to zero.
#### 6、**Is the security of smart contracts guaranteed?**
PairEx takes the security of smart contracts very seriously and acknowledges the inherent risks associated with their use. As a result, we employ a range of measures and best practices to mitigate these risks, such as conducting thorough audits, testing, and implementing proper coding standards. We also use well-established smart contract frameworks and platforms to increase the security of our smart contracts. While we cannot guarantee the complete security of smart contracts, we believe that with the right precautions, their security can be significantly improved. Our commitment to security ensures that our users can trade on our platform with confidence.
#### 7、How is the Net PnL of the position calculated?
Net PnL includes unrealized profit and losses on positions, closing fees, rollover fees, and funding fees
Net PnL = UnrealizedPnl - Rollover fees - Funding fees - Closing fees
UnrealizedPnl = (Position Size / Open price)\*Price difference
Accumulated Funding fee may be expenses or income
For example, let's say a user opens a long position with a position size of 100 USDT at an open price of 2000 USDT per BTC, and the current market price is 2100 USDT per BTC. The unrealized PnL would be calculated as follows:
Unrealized PnL = (100 / 2000) \* (2100 - 2000) = 5 USDT
Assuming there were no rollover fees, funding fees, or capital costs, the net PnL would be 5 USDT. However, if there was a closing fee of 0.08%, the final net PnL would be 4.996 USDT.
---
# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.
## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.
Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:
```
GET https://doc.pairex.io/help/faq.md?ask=&goal=
```
`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.
Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.