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+# Fees
+
+Contractless transactions have base fees. These are the minimum fees required for validation.
+
+Wallet software may allow users to increase fees above the base minimum. Higher fees can make a transaction more attractive for miners when they are selecting pending transactions from the mempool.
+
+Fees are paid in the base coin for the network. On testnet this is usually displayed as `CLTC`. On mainnet this is usually displayed as `CLC`.
+
+## Base Fee Chart
+
+| Transaction | Base Fee |
+| --- | ---: |
+| Base coin transfer | `1%` of transfer amount |
+| Token transfer | `1.00000000` |
+| NFT transfer | `1.00000000` |
+| Numbered NFT transfer | `1.00000000` |
+| Create token | `500.00000000` |
+| Issue more tokens | `100.00000000` |
+| Create NFT | `0.50000000` |
+| Marketing record | `1.00000000` |
+| Swap | `1.00000000` per signer |
+| Create loan | `3.00000000` |
+| Loan payment | `0.01000000` |
+| Collateral claim | `3.00000000` |
+| Burn token or NFT | `0.00010000` |
+| Vanity address registration/update | `5.00000000` |
+| Create storage key | `500.00000000` |
+| Write storage value | `1.00000000` |
+
+## Transfer Fees
+
+Base coin transfers use a percentage fee:
+
+```text
+minimum fee = transfer amount * 1%
+```
+
+Token and NFT transfers use the fixed non-base transfer minimum:
+
+```text
+1.00000000
+```
+
+For numbered NFT collection transfers, the transfer amount must be exactly one NFT item, and the transfer fee is still the fixed non-base transfer fee.
+
+## Swap Fees and Tips
+
+Each swap signer pays the fixed swap base fee:
+
+```text
+1.00000000 per signer
+```
+
+Swaps also include asset-denominated miner tips for the trade sides.
+
+Each side has two separate miner payments:
+
+| Field | Paid By | Paid In | Paid To | Notes |
+| --- | --- | --- | --- | --- |
+| `txfee1` | `sender1` | Base coin | Miner | Must be at least `1.00000000`. |
+| `txfee2` | `sender2` | Base coin | Miner | Must be at least `1.00000000`. |
+| `tip1` | `sender1` | `ticker1` / side 1 asset | Miner | For fungible assets, must be at least 1% of `value1`. For NFT sides, must be `0`. |
+| `tip2` | `sender2` | `ticker2` / side 2 asset | Miner | For fungible assets, must be at least 1% of `value2`. For NFT sides, must be `0`. |
+
+The tips are not sent to the swap counterparty. They are paid to the miner who includes the swap in a block.
+
+For fungible swap sides, spendability is checked against the offered amount plus the tip:
+
+```text
+sender1 must have value1 + tip1 of ticker1
+sender2 must have value2 + tip2 of ticker2
+```
+
+Each sender must also have enough base coin for their own base transaction fee.
+
+## Loan Payment Fees and Tips
+
+Loan payments have a base fee:
+
+```text
+0.01000000
+```
+
+Loan payments also include an asset-denominated miner tip.
+
+| Field | Paid By | Paid In | Paid To | Notes |
+| --- | --- | --- | --- | --- |
+| `txfee` | Borrower / payer | Base coin | Miner | Must be at least `0.01000000`. |
+| `payback_amount` | Borrower / payer | Loan asset | Lender | Counts toward the loan balance. |
+| `tip` | Borrower / payer | Loan asset | Miner | Must be at least 1% of `payback_amount`. |
+
+The lender receives only the `payback_amount`. The miner receives the base fee and the tip.
+
+Spendability is checked against the payment amount plus the tip:
+
+```text
+borrower must have payback_amount + tip of the loan asset
+borrower must also have txfee in base coin
+```
+
+Pending loan payments in the mempool also reserve the tip amount. This prevents a borrower from creating multiple pending payments that appear valid only because the tips were ignored.
+
+## Storage Lookup Fees
+
+Storage write fees are normal transaction fees and are listed in the base fee chart.
+
+Storage lookups are different. A node operator may charge a per-byte lookup fee for returning app storage data through RPC. That fee is configured by the node operator in `settings.ini` and is not a fixed network-wide transaction fee.
+
+Use `lookup_storage_cost` to quote storage lookup fees before paying for a lookup. See [Data Storage](src/branch/main/docs/DATA_STORAGE.md).
+
+## lookup_largest_txfee
+
+`lookup_largest_txfee` asks a configured node for the largest transaction fee currently known from its mempool data.
+
+This can help users or wallet software understand what base fee level is currently competing for miner selection.
+
+For swaps, the lookup compares both base fee fields, `txfee1` and `txfee2`. It does not include asset-denominated swap tips.
+
+For loan payments, the lookup uses the base `txfee`. It does not include the asset-denominated loan payment tip.
+
+Usage:
+
+```bash
+./lookup_largest_txfee
+```
+
+Interactive prompts:
+
+```text
+Please enter the path to your wallet file:
+What is your wallet decryption key?
+```
+
+Expected output:
+
+```json
+{
+  "largest_tx_fee": "1.00000000"
+}
+```
+
+If the peer has no mempool transactions, the tool returns:
+
+```json
+{
+  "largest_tx_fee": "0.00000000"
+}
+```
+
+The value is only a snapshot from the peer that answered the request. Different nodes may temporarily report different mempool fee data.