A failed SpookySwap swap usually means the transaction could not meet the price, balance, approval, or network condition written into it. This guide settles which condition failed and what to change first, so the same transaction is not repeatedly submitted. It applies when a wallet is connected to the intended EVM network, the token contract has been checked, and the swap has not already been confirmed on-chain.
“INSUFFICIENT_OUTPUT_AMOUNT” on SpookySwap: what it means
This error does not mean the wallet has lost funds. It means the pool could no longer deliver at least the minimum amount of the output token specified when the transaction was signed. The usual cause is a price move while the transaction was waiting, though a thin pool or a large trade can produce the same result.
SpookySwap trades against liquidity pools rather than matching a buyer with a particular seller. In that automated market maker model, a trade itself moves the relative pool price; less liquidity at the relevant price point means more price impact. The project’s swap documentation explains that its interface estimates this effect and that slippage tolerance is the allowed movement beyond it.
Do not begin by setting a very high slippage tolerance. First reduce the trade size or split it into smaller transactions. If the quoted output improves materially, pool depth—not a broken button—was the issue. If the token is volatile, refresh the quote, set a tolerance appropriate to the trade, and submit again only after checking the minimum received figure.
3 checks before changing SpookySwap settings
- Check the network. The wallet must be on the network where the selected token and pool exist. A familiar symbol does not prove that the token contract is the same asset on every chain.
- Check the contract address. Select or add a token by its full contract address, not its name or ticker. Permissionless pools can contain tokens with duplicated symbols and tokens whose own transfer rules prevent a sale.
- Check the transaction in the explorer. A reverted transaction provides the contract’s actual failure reason. A pending transaction is a different problem: wait for it, replace it with the same nonce if the wallet supports that workflow, or resolve it before sending another swap.
This order matters. Adjusting slippage cannot repair a wrong network, an unsupported token contract, or a transaction that is still occupying the wallet’s nonce.
1 approval transaction: why it is separate
Before an ERC-20 token can be swapped, the router normally needs permission to move the input token from the wallet. An ERC-20 token is a fungible-token standard whose approve and allowance functions let an owner grant a spender that permission. That approval is an on-chain transaction, so it can fail, remain pending, or succeed while the later swap still fails for a different reason.
If the interface returns to “Approve,” open the wallet activity and confirm whether the approval actually completed on the same network. If it did, refresh the interface and check that the wallet’s available balance is not lower than the proposed input. If the approval failed, inspect that transaction instead of repeatedly approving: a missing native-token balance for gas, a wallet connection problem, or token-specific contract behavior may be blocking it.
Approval is also a moment to slow down. Verify the spender shown in the wallet, the token contract, and the allowance amount before signing. An approval is not a swap quote and does not lock in a price.
0 balance for gas: the network-level failure
A wallet can hold the input token and still be unable to swap it. Smart-contract calls require the network’s native token to pay gas. Gas is the unit measuring computational work, and a fee is charged even when a transaction executes and then reverts, as Ethereum’s gas documentation explains.
Keep enough of the correct native asset in the wallet for both the approval, if needed, and the swap. Do not use the entire native-token balance as the input amount. If a transaction stays pending, the problem may be fee settings, an RPC connection, or network congestion; it is not evidence that increasing slippage will help.
| What appears | Most likely condition | First action |
|---|---|---|
| “Insufficient output amount” | Price moved beyond the minimum received | Refresh quote; reduce size before raising tolerance |
| “Approve” repeats | Allowance has not completed or is on another network | Inspect the approval transaction and wallet network |
| Transaction pending | Nonce, fee, or RPC issue | Check the explorer before sending another swap |
| Swap button cannot proceed | Missing native token for gas or wrong network | Fund gas and switch to the intended chain |
10 August 2026: use the documented SpookySwap route
As of 10 August 2026, the official documentation describes SpookySwap V3 as an AMM DEX built on UNIV3 for EVM-compatible networks and lists swap, troubleshooting, contract, and token-address resources. That current SpookySwap documentation index is the reference to use when confirming the network and contracts involved.
The practical recommendation is to open the project’s swap interface at https://spookyswap.dev/, connect the intended wallet network, and treat the wallet confirmation and block-explorer result as the record of what happened. A failed SpookySwap transaction is usually specific enough to diagnose once the error, token address, allowance, native gas balance, and pending nonce are checked in that order.