Flash Loan Calculator

Calculate arbitrage profit and flash loan fees

Trade Setup

How much you want to borrow

Flash loan provider

Price on exchange A

Price on exchange B

Estimated transaction gas fee

Expected slippage on swaps

Flash Loan Strategies

Simple Arbitrage Win

Borrow $100k. ETH at $2000 on Uniswap, $2020 on Sushiswap. Buy 50 ETH, sell for $101k. Gross: $1k. Aave fee: $90. Gas: $150. Slippage: $300. Net: $460. Clean profit in one transaction.

Failed Trade

Borrow $50k. Price gap $5. Gross: $250. Fee: $45. Gas: $200. Slippage: $150. Net: -$145 loss. Transaction reverts. Lost gas fee. Price gap too small. Need $8+ gap to break even.

Liquidation Profit

Borrow $500k. Liquidate underwater position. Get 10% bonus. Repay debt $450k. Gross: $50k. Fee: $450. Gas: $300. Net: $49,250. Big wins on liquidations. Monitor health factors.

Collateral Swap

Borrow $200k. Repay DAI loan. Withdraw ETH collateral. Swap to USDC. Deposit USDC. Borrow DAI again. Repay flash loan. Changed collateral type. Fee: $180. Gas: $250. Total cost: $430.

Multi-Hop Arb

Borrow $1M. ETH→WBTC→USDC→ETH across 3 DEXs. Each hop 0.5% gain. Total: 1.5% = $15k gross. Fee: $900. Gas: $400. Slippage: $3k. Net: $10,700. Complex but profitable with size.

Self-Liquidation

Your position near liquidation. Borrow $300k. Repay your loan. Withdraw collateral. Avoid 10% liquidation penalty. Fee: $270. Gas: $200. Saved: $30k penalty. Smart move when health factor drops.

Flash Loan FAQ

What's a flash loan?

Borrow millions with zero collateral. Must repay same transaction. If can't repay, reverts. Used for arb and liquidations.

How much does it cost?

Aave: 0.09%. Balancer: 0%. Plus gas $50-500. Borrow $1M on Aave = $900 fee + gas.

Can I lose money?

Only gas if trade fails. Transaction reverts if unprofitable. But you lose gas fee. Test carefully first.

How to find opportunities?

Monitor price differences across DEXs. Watch liquidation bots. Track on-chain arb. Use APIs and bots.

Minimum profit needed?

Cover fee + gas + slippage. Usually $200+ to be worth it. Bigger loans = better % returns.

Which protocol best?

Aave: most liquidity. Balancer: 0% fee. dYdX: discontinued. Start with Aave for reliability.

Need coding skills?

Yes. Write Solidity smart contract. Handle callbacks. Test on testnet. Not for beginners. High technical barrier.

Competition level?

Very high. MEV bots dominate. Need fast execution. Opportunities disappear in seconds. Requires automation.

Recommended Tools

💬 User Comments

Share your thoughts and feedback about this tool

Please login to leave a comment

No comments yet. Be the first to share your thoughts!

×

Rate this tool

Select a rating