Why the estimated amount shown on screen changes by the time the swap completes

05 September 2026

The estimated amount you see on screen changes by the time the swap completes because the quoted rate is based on market conditions at the moment you start the swap, while the final rate is determined when the transaction actually executes on the blockchain. This delay - often just seconds, sometimes minutes - lets market price movement, network congestion, and the internal mechanics of the exchange alter the amount you receive.

The core reason: timing mismatch

When you initiate a swap on southkoreacoin.fun, the system locks in a preliminary rate using live data from the exchanger's liquidity pool. That rate is an estimate, not a guarantee. The swap itself must travel through several steps: your wallet broadcasts the transaction, the exchanger's smart contract processes it, and the network confirms it. Each step takes time. During that window, the price of either coin can shift, especially in volatile markets. A 1% move in thirty seconds is common. If the market moves against you, the final amount drops. If it moves in your favor, you might get slightly more - though the system typically builds in a small buffer to protect against sudden adverse moves, so you rarely see a pleasant surprise.

Network fees and confirmation delays

Network congestion plays a role. Ethereum, Binance Smart Chain, and other blockchains have variable transaction fees. When you set a gas price, the exchanger uses that to estimate the network cost. If congestion spikes, the transaction might take longer to confirm. During that extra time, the price can change. Worse, if you set too low a gas price, the transaction could stall or fail, forcing a re-estimate at a worse rate. The system does not re-quote automatically; it uses the original estimate until the swap executes, so the final amount reflects the actual network conditions at settlement.

The exchanger's spread and slippage

The exchanger does not offer a single fixed price. It quotes a rate that includes its spread - the difference between the buy and sell price of the asset. That spread is dynamic, widening when liquidity is thin or volatility high. When you confirm the swap, the system reserves a portion of the liquidity pool at that spread. But if another user trades the same pair before your transaction lands, the pool's balance shifts, and the effective rate changes. This is slippage. The system shows an estimated amount assuming current pool depth, but if your trade is large relative to the pool, the actual execution price drifts. The estimate accounts for this with a slippage tolerance setting - usually 0.5% to 1% - but if the market moves beyond that, the swap may fail or execute at a worse rate.

Why the number on screen is not a promise

The estimated amount is a snapshot. It is computed from the best available data at that instant. The system cannot freeze the market for you. Every decentralized exchange works this way: the quote you see is a prediction, not a contract. Centralized exchanges sometimes offer "guaranteed" quotes for a fee, but this platform routes through decentralized liquidity, where no single entity can lock a price. The number changes because the market changes, and the swap is always a moment behind.

What this means for your costs

The difference between the estimated and received amount is a real cost. It is not a fee you see on a receipt, but it reduces what you get. This cost is part of the total expense of a crypto swap, alongside the explicit spread and network fees. Understanding it helps you avoid surprises. If you want to dig deeper into the full breakdown of where your money goes, the hub page "What a crypto swap actually costs" covers the spread, network fees, and the gap between quoted and received amounts in more detail. That page is the next logical read if you are tracking every satoshi.

Practical takeaways

• Check the estimated amount just before you confirm, then watch the market for a few seconds. If it is moving fast, expect a larger change.
• Use a higher gas price during congestion to reduce confirmation delays.
• Keep your trade size modest relative to the pool to minimize slippage.
• Accept that the final amount will rarely match the estimate exactly. A 0.5% to 2% variance is normal. Anything larger suggests unusual market conditions or a liquidity issue.

The number on screen is a guide, not a guarantee. The swap completes at the market's next breath, and that breath changes the amount.

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