Utilization Rate

What Is Utilization Rate?

Utilization rate measures the percentage of a lending pool's total deposited assets that are currently borrowed. It is the single most important metric in DeFi lending because it directly determines both borrowing costs and lender yields. The formula is straightforward:

Utilization Rate = Total Borrows / Total Deposits

For example, a pool with $80 million borrowed out of $100 million deposited has an 80% utilization rate. This means 80% of the supplied capital is actively earning interest from borrowers, while 20% remains available for lender withdrawals.

How Utilization Rate Drives Interest Rates

Most DeFi lending protocols use an interest rate model that ties borrowing and lending rates directly to the utilization rate of each pool. The relationship is designed to balance two competing needs: keeping borrowing costs attractive enough to generate demand, while ensuring lenders can always withdraw their funds.

At low utilization (say, 20-30%), borrowing rates are minimal because there is an abundance of idle capital. The protocol wants to encourage borrowing to put that capital to work. As utilization climbs, rates increase gradually, reflecting growing demand for the available liquidity.

The critical design feature in most protocols is the kink point (also called the optimal utilization rate). This is a predetermined threshold, often set between 70% and 90% depending on the asset, beyond which interest rates escalate sharply. For instance, Aave might set the kink at 80% for a USDC pool. Below 80% utilization, the borrowing rate might increase linearly from 2% to 5%. Above 80%, it could jump steeply, reaching 50% or more at full utilization.

This steep slope above the kink serves a vital purpose: it creates strong financial incentives for borrowers to repay loans and for new lenders to supply capital, preventing the pool from reaching 100% utilization where no withdrawals would be possible.

Why Utilization Rate Matters for Borrowers

For borrowers, monitoring utilization rate is essential for managing the cost of a loan. A pool sitting at 50% utilization will have moderate borrowing rates, but a sudden influx of borrowing demand could push utilization above the kink point and dramatically increase the variable rate you are paying.

Savvy borrowers check utilization before opening a position and keep an eye on trends. If a pool is already near its optimal utilization threshold, it may be worth comparing rates on alternative protocols or chains. Aggregator platforms consolidate rates across multiple lending protocols, making it straightforward to identify pools with lower utilization and more favorable borrowing terms.

Borrowers should also be aware that utilization can spike during periods of market stress. When prices drop and liquidations increase, borrowers who want to repay may compete with liquidation bots for available liquidity, temporarily pushing utilization and rates even higher.

Why Utilization Rate Matters for Lenders

For lenders, utilization rate directly determines the supply rate (the yield earned on deposited assets). The supply rate is calculated as:

Supply Rate = Borrowing Rate x Utilization Rate x (1 - Reserve Factor)

Higher utilization generally means higher yields because a larger portion of the deposited capital is earning interest. However, there is a trade-off: extremely high utilization means less liquidity is available for withdrawals. If a lender needs to exit their position during a period of near-100% utilization, they may need to wait until borrowers repay or new deposits arrive.

This is why the kink mechanism exists. By making borrowing prohibitively expensive above the optimal threshold, protocols create a self-correcting system that typically keeps utilization in a healthy range where lenders earn reasonable yields while maintaining withdrawal access.

Utilization Rate Across Different Asset Types

Different assets tend to have different utilization patterns. Stablecoins like USDC and USDT often see high utilization because the demand for dollar-denominated borrowing is consistently strong. Volatile assets like ETH or wrapped BTC may have lower utilization rates, reflecting lower borrowing demand or higher collateral requirements.

Protocol governance teams set the kink point and rate curve parameters for each asset individually, calibrating them based on the asset's volatility, liquidity depth, and historical utilization patterns.

Practical Tips for Monitoring Utilization

Before entering any lending or borrowing position, check the current utilization rate and recent trends. Most protocol dashboards display this information prominently. Look at whether utilization has been stable, trending up, or volatile. A pool that frequently spikes above its kink point may indicate structural demand imbalance, which could mean persistent high borrowing costs or, for lenders, attractive but potentially illiquid yields.