# Bids & Asks Delta

## Definition

**Bid-Ask Delta** measures the **net difference between buy-side liquidity (bids) and sell-side liquidity (asks)** within the order book at specific **depth levels**. It highlights the **imbalance between passive buy and sell orders**, offering insight into supply and demand dynamics across different price ranges.

Bid-Ask Delta = Total Bids − Total Asks

#### **Depth Parameters:**

The **Bid-Ask Delta** can be calculated across multiple **order book depth levels**, each representing a specific range from the mid-price:

* **Quote:** Best bid and ask prices.
* **1% Depth:** Orders within 1% of the mid-price.
* **2% Depth:** Orders within 2% of the mid-price.
* **5% Depth:** Orders within 5% of the mid-price.
* **10% Depth:** Orders within 10% of the mid-price.
* **20% Depth:** Orders within 20% of the mid-price.
* **Full Book:** All visible orders in the order book.

Each depth level offers a unique perspective on liquidity imbalances, with smaller ranges reflecting short-term orderbook and larger ranges showing broader liquidity trends.

#### **Key Insights:**

* **Positive Delta:** Indicates more buy-side liquidity (bids exceed asks), suggesting stronger demand.
* **Negative Delta:** Indicates more sell-side liquidity (asks exceed bids), suggesting stronger supply.
* **Depth Variance:** Imbalances at deeper levels may indicate hidden liquidity or strategic positioning.

The **Bid-Ask Delta** serves as a **powerful tool for assessing liquidity imbalances across multiple depth levels**, helping traders and analysts identify market sentiment, liquidity zones, and potential price pressure points.
