When you exchange cryptocurrency, the rate you receive can vary depending on which type of swap you choose. Understanding the difference between floating-rate and fixed-rate swaps helps you make better decisions — especially in volatile market conditions.
What Is a Floating Rate Swap?
In a floating rate swap, the exchange rate is not locked in when you create the swap. Instead, the final rate is determined at the moment your deposit is received and confirmed on the blockchain.
Advantages of floating rate swaps: Typically offer better base rates than fixed rate swaps. Because the liquidity provider does not need to guarantee a specific rate in advance, they do not need to embed a risk premium. More liquidity is available and more pairs are supported.
Disadvantages: The primary disadvantage is uncertainty. You do not know the exact amount you will receive until the swap executes. In periods of extreme market volatility, the rate can move meaningfully between quote and execution.
SyntheticSwap uses floating rates because they consistently provide the most fair market price for most swaps. The platform's AI-powered routing engine selects the best liquidity source for each transaction.
What Is a Fixed Rate Swap?
In a fixed rate swap, the exchange rate is locked at the time you create the swap. Regardless of what the market does while your transaction is in flight, the output amount is guaranteed — as long as you send your funds within the specified time window (typically 10 to 30 minutes).
Advantages: The primary advantage is certainty. You know exactly how much you will receive before you send. This is valuable when swapping a large amount, when the market is experiencing high volatility, or when you need the output amount for accounting purposes.
Disadvantages: Fixed rate swaps typically come with slightly worse exchange rates. The liquidity provider assumes the rate risk for the duration of the lock window and charges a small premium. Not all pairs and amounts are available at fixed rates.
Which Should You Choose?
Use floating rate for most standard swaps where the expected rate is acceptable and you are comfortable with minor variance. Floating rate is almost always the better economic choice for routine swaps in normal market conditions.
Use fixed rate when:
- The market is experiencing extreme volatility (more than 2-3% movement per hour)
- You are swapping a large amount and need predictability for accounting or reporting
- You have a specific output amount requirement
- You have a clear time window to send and are ready to act promptly
How Liquidity Providers Set Exchange Rates
Liquidity providers calculate exchange rates based on current market price from trading venues, their own reserve balances, and their operational margin. For floating rate swaps, this calculation happens at the moment your deposit is confirmed. For fixed rate swaps, it happens when you request the quote, and the provider bears the risk of price movements until your transaction is processed.
Slippage vs. Rate Type Variance
Slippage is the difference between the expected price and actual execution price, caused by price movement during the processing window. It affects floating rate swaps.
Rate type variance is the guaranteed uncertainty of a floating rate — you know in advance that the final rate will be whatever the market rate is at processing time. Fixed rate swaps eliminate slippage but include a premium for that guarantee.
A Note on Network Fees
Regardless of which rate type you choose, network fees (the cost of the blockchain transaction itself) are deducted from the output amount. These fees are set by the network, not the exchange. Always check the estimated network fee before confirming your swap.
Conclusion
Both rate types serve valid purposes. For everyday swaps in normal conditions, floating rate delivers the best market price with minimal friction. For high-stakes swaps where certainty of output matters more than getting the absolute best rate, fixed rate provides peace of mind and operational predictability.
