Direct Answer
Loan-to-value measures debt relative to collateral value, while a liquidation threshold defines when collateral no longer safely supports debt. A health factor is a protocol-specific summary of that relationship. A health factor near the liquidation boundary is not a target; it is a warning that ordinary price movement, debt growth, oracle updates, or transaction delays may trigger liquidation.
Key Takeaways
- LTV describes current leverage; maximum LTV describes borrowing capacity; liquidation threshold defines a separate failure boundary.
- Health-factor formulas differ, but values at or below the protocol's threshold can permit liquidation.
- Collateral volatility and debt growth can reduce safety even when the user takes no action.
- Oracle prices—not the user's preferred chart—usually determine eligibility.
- Prudent positions use stress-tested buffers and predefined responses rather than borrowing to the maximum.
What This Page Covers
This page explains the measurements and shows how to model a borrowing position. Examples are simplified and must not be substituted for live protocol formulas or parameters.
LTV and Borrowing Capacity
Loan-to-value is commonly expressed as:
LTV = debt value ÷ collateral value
If collateral is worth $10,000 and debt is worth $4,000, LTV is 40%. A protocol may allow a higher maximum LTV, but that limit only tells the user whether a new borrow can be opened. It does not necessarily mark liquidation.
Protocols may apply asset-specific LTVs and weighted calculations across multiple collateral assets. Some assets can be supplied but not used as collateral. Caps, isolation modes, efficiency modes, debt ceilings, or siloed borrowing can further change capacity.
Liquidation Threshold
A liquidation threshold is the point at which adjusted collateral no longer covers debt under protocol rules. If the threshold is 80%, a simplified position with $10,000 collateral may become liquidatable around $8,000 debt, before fees and formula details.
The distance between current LTV and liquidation threshold is the raw buffer. The useful buffer must also account for volatility, liquidity, oracle cadence, debt interest, gas, and the user's ability to act. A ten-percentage-point buffer can be inadequate for a volatile asset that can move that much before a transaction confirms.
Health Factor
A common conceptual formula is:
health factor = liquidation-adjusted collateral value ÷ debt value
A value above 1 indicates adjusted collateral exceeds debt. A value at or below 1 may permit liquidation. Protocols can calculate weighted collateral, debt, and thresholds differently, so the displayed value and documentation are authoritative for that market.
Health factor is a summary, not a diagnosis. It does not show which asset creates the risk, how liquid the collateral is, whether an oracle is delayed, or how much a liquidation would cost. Users should inspect the underlying components.
How Liquidations Work
When a position crosses the eligibility boundary, a liquidator can repay some debt and receive collateral, usually with an incentive. The protocol may limit how much debt can be repaid at once through a close factor or similar rule.
Liquidation protects suppliers by reducing bad debt, but it creates loss for the borrower through collateral sale, penalty, fees, and adverse timing. In fast markets, multiple liquidations can occur before a user restores the position. Adding collateral or repaying debt after the boundary is crossed may be too late.
Stress Testing the Buffer
Model at least four stresses:
- collateral falls while debt stays constant;
- debt grows while collateral stays constant;
- collateral falls and borrowed asset rises;
- oracle or network conditions delay a rescue transaction.
For multi-asset positions, test correlation breaks. For stablecoin pairs, test depegs in both directions. A position that is safe only under normal correlation is not conservatively structured.
Practical Decision Framework
Set a three-zone policy:
- Normal zone: health factor comfortably above the action threshold; routine monitoring.
- Action zone: predefined level at which the user repays debt, adds high-quality collateral, reduces exposure, or exits.
- Emergency zone: level at which only the fastest reliable action is attempted and no new risk is added.
The action zone must be far enough from liquidation to allow for price movement, oracle updates, network congestion, and human response time.
Worked Example
Collateral: 5 ETH at $2,000 = $10,000
Debt: 4,000 stablecoin units
Liquidation threshold: 80%
Simplified health factor:
($10,000 × 0.80) ÷ $4,000 = 2.0
If ETH falls to $1,250:
Collateral value = $6,250
Adjusted collateral = $5,000
Health factor = $5,000 ÷ $4,000 = 1.25
If debt has grown to $4,200, health factor falls to about 1.19. A further 16% collateral decline could approach the liquidation boundary. The original 40% LTV did not guarantee lasting safety; asset movement and debt growth changed the position.
Common Mistakes
- Confusing maximum LTV with liquidation threshold.
- Using the protocol minimum as a personal safety target.
- Monitoring a market price that differs from the protocol oracle.
- Ignoring accrued interest and variable borrow rates.
- Assuming stablecoins cannot move against each other.
- Adding correlated collateral and treating it as diversification.
- Waiting for the health factor to approach 1 before planning a response.
Risks and Limitations
Liquidation rules, thresholds, bonuses, close factors, and oracle safeguards differ by protocol, asset, and mode. Oracle prices can diverge from exchange prices. Network congestion can delay rescue transactions. Collateral can become illiquid or be frozen. Governance can change parameters.
The examples omit taxes, fees, slippage, liquidation bonuses, and exact weighted formulas. Verify live values and simulate adverse scenarios.
Practical Checklist
- Record collateral quantities, oracle values, debt quantities, and rates.
- Identify maximum LTV and liquidation threshold for each asset.
- Calculate current LTV and health factor independently.
- Set action and emergency thresholds above liquidation.
- Stress prices, rates, depegs, and transaction delays.
- Keep repayment assets and gas accessible.
- Configure independent alerts rather than relying on one interface.
- Know the exact repay and add-collateral steps.
- Reduce leverage when the response window becomes uncertain.
Frequently Asked Questions
What is a safe health factor?
There is no universal safe number. It depends on asset volatility, debt behavior, oracle design, liquidity, network speed, and the user's action plan.
Can I be liquidated if my collateral rises?
Yes, if the borrowed asset rises faster, debt accrues, thresholds change, or another collateral component falls.
Does adding collateral always help?
It generally increases adjusted collateral, but adding a volatile, correlated, bridged, or risky asset can create new dependencies.
Can I stop liquidation after it begins?
Not reliably. Once eligible, liquidators may execute immediately. Prevention and early action are more dependable than reaction.
Why does the protocol price differ from an exchange?
Protocols use specified oracle sources and update rules. The value used for liquidation may not match a single venue's last trade.
Summary
LTV, liquidation threshold, and health factor are related but distinct. A sound borrower uses them to maintain a stress-tested operating buffer, not to maximize leverage. Monitoring and response plans must account for prices, rates, oracle behavior, liquidity, and execution delay.
Suggested Next Lesson
Continue to Where Stablecoin Yield Comes From. Return to the DeFi Lending & Borrowing subcategory or the DeFi & Yield learning hub at any time.
Educational Disclaimer
Educational disclaimer: Educational information only; not investment, tax, legal, or personalized financial advice. DeFi positions can lose some or all committed assets through market movement, liquidation, smart-contract failure, governance action, oracle failure, bridge failure, stablecoin instability, operational mistakes, fraud, or other causes.