Skip to main content
Calcimator

Flash Loan Calculator

Size a flash loan arbitrage opportunity by calculating net profit after protocol fees, DEX fees, gas costs, and slippage. Determine break-even spreads and daily/monthly profit projections.

Inputs

%
%
%

Results

Net profit per execution ($)

$352.50

≈ 6 tanks of gas

Profitable?Yes
Gross profit ($)$1,500.00
Total costs ($)$1,147.50
Flash loan fee ($)$90.00
DEX fees ($)$604.50
Slippage cost ($)$403.00
Break-even spread (%)1.15%
Daily profit ($)$1,762.50
Monthly profit ($)$52,875.00
ROI on gas capital (%)705%
How to Use This Calculator
  1. Enter the Flash Loan Amount ($) — the size of the uncollateralized loan from a protocol like Aave.
  2. Set the Flash Loan Fee % (Aave = 0.09%) and the Buy Price and Sell Price on the two venues you are arbitraging.
  3. Enter DEX Swap Fee % (Uniswap V3 pools are 0.05%, 0.3%, or 1%) and expected Slippage %.
  4. Set Gas Cost ($) for the entire flash loan transaction and Executions per Day to project daily income.
  5. Review Net Profit per Execution, Break-Even Spread %, and Daily/Monthly Profit — a negative net profit means the trade is not viable at current prices.

How the result changes with Buy price ($)

Buy price ($)Net profit per execution ($)
10,000,000-$100,629.90
35,000,000-$100,637.11
65,000,000-$100,638.45
90,000,000-$100,638.88

What each input means

Flash loan amount ($)
Amount borrowed via flash loan (repaid in same transaction).
Flash loan fee (%)
Protocol fee for the flash loan (Aave = 0.09%, dYdX = 0%).
Buy price ($)
Token price on the cheaper venue (where you buy).
Sell price ($)
Token price on the more expensive venue (where you sell).
DEX swap fee (%)
Trading fee per swap (Uniswap V3 typical: 0.05%-1%).
Slippage (%)
Expected slippage on each swap based on liquidity depth.
Gas cost ($)
Total gas cost for the flash loan transaction in USD.
Executions per day
Expected number of profitable executions per day.

What each result means

Net profit per execution ($)
Profit after all fees, slippage, and gas. Must be positive to be viable.
Profitable?
Whether the trade is profitable after all costs.
Gross profit ($)
Profit from the price difference before any costs.
Total costs ($)
Sum of flash loan fee, DEX fees, slippage, and gas.
Flash loan fee ($)
Fee paid to the flash loan protocol.
DEX fees ($)
Trading fees across buy and sell swaps.
Slippage cost ($)
Estimated cost of price slippage on both trades.
Break-even spread (%)
Minimum price spread needed to cover all costs.
Daily profit ($)
Projected daily profit if executed at target frequency.
Monthly profit ($)
Projected monthly profit (30 days).
ROI on gas capital (%)
Return relative to the only capital at risk (gas cost).

How this is calculated

Worked example, using the default values

  1. Identify Input Parameters
    4 parameters
    Flash loan amount ($) = 100000, Flash loan fee (%) = 0.09, Buy price ($) = 1000, Sell price ($) = 1015 = 8 input(s) provided
  2. Calculate Net profit per execution
    Net profit per execution = grossProfit - totalCosts
    352.5 = $352.5
  3. Calculate Profitable?
    Yes = Yes
  4. Calculate Gross profit
    Gross profit = sellGross - loanAmount
    1500 = $1,500

Engine last updated . Checked against 2 independently-derived tests — how we verify calculators.

Related Calculators

The questions that sit next to this one — chosen by subject, including calculators filed under a different category.

Crypto Advanced

Cross-Chain Arbitrage Calculator

Calculate potential profit from cross-chain arbitrage opportunities after accounting for bridge fees, gas costs, and slippage on both chains.

Crypto Advanced

MEV Calculator

Estimate Maximal Extractable Value (MEV) opportunity sizing for sandwich attacks, accounting for gas costs, builder tips, competition, and success rates.

Crypto Advanced

Lending Protocol APY Calculator

Calculate net APY from DeFi lending protocols like Aave or Compound, accounting for supply APR, borrow APR, token rewards, compounding frequency, and health factor.

Income Optimization

Geographic Arbitrage

Rough spending adjustment when moving between cost-of-living indexes (same income).

More in Investing & Retirement.