Fees and pricing

Every quote shows exactly what the user pays, in US dollars, line by line. Nothing is hidden in the exchange rate: the fees add up to the difference between what the user sends and what they receive, plus the gas they pay.

Fee types

A quote’s fees has a total (totalUsd) and a list of items. Each item has a kind and an amount in dollars.

`kind`	What it covers	Shows up on
`network`	Gas for every transaction in the swap, including the user’s own. Across chains, it also covers Circle’s fee when the solver moves USDC between chains.	Cross-chain and same-chain swaps
`solver`	Across chains, the solver’s margin, plus price impact and DEX fees when it has to buy or sell a token. On one chain, what the route loses to price impact and DEX fees.	Cross-chain and same-chain swaps
`partner`	Your fee as a partner, if your account has one.	Cross-chain swaps
`protocol`	Tern’s fee.	Same-chain and private swaps
`privacy`	The privacy pool’s fee and the gas to submit the transaction, paid in STRK. It replaces `network`, since the user doesn’t send a transaction themselves.	Private swaps

A fee can be "0.00". It’s listed so you can see it was counted. New kinds may appear over time, so show any kind you don’t recognize by its amount.

Other numbers in a quote

Field	What it means
`from.usd`, `to.usd`	What the user sends and receives, in dollars, at the time of the quote.
`fees.totalUsd`	All the fees added up.
`costBps`	The total cost as a share of what the user sends, in basis points (1 bps = 0.01%), gas included.
`priceImpactBps`	How much of the cost comes from price impact and DEX fees. It’s part of the `solver` fee.
`sourceGas`	The gas the user’s wallet pays to send the swap or deposit, in the chain’s gas token and in dollars.
`etaSecs`	Roughly how many seconds from the deposit being seen to the user being paid.

Dollar amounts are strings with two decimals, rounded down. A swap’s status keeps the numbers from when it was quoted.

An example

Here’s a quote for 1,000 USDC on Base to USDC on Starknet:

{
  "from": { "chain": "base", "amount": "1000000000", "usd": "1000.00" },
  "to":   { "chain": "starknet", "amount": "998820000", "usd": "998.82" },
  "fees": {
    "totalUsd": "1.20",
    "items": [ { "kind": "network", "usd": "0.70" }, { "kind": "solver", "usd": "0.50" } ]
  },
  "costBps": 12,
  "priceImpactBps": 0,
  "sourceGas": { "amount": "5800000000000", "usd": "0.02" },
  "etaSecs": 40
}

The user sends $1,000.00 and receives $998.82, a difference of $1.18.
They also pay $0.02 in gas for the deposit.
So the total cost is $1.20, or 0.12%. That’s fees.totalUsd and costBps.
The $0.70 network fee is gas on both chains, including the user's $0.02. The $0.50 is the solver’s margin.
Price impact is 0, because swapping USDC for USDC needs no trade.

What to show your users

What they’ll receive: to.amount, plus to.minAmount as the minimum when there is one.
The total cost: for example, “Total cost $1.20 (0.12%)”.
The breakdown, if they ask: each fee, and price impact when it isn’t zero.
Only what’s there: every number except the amounts is optional. Leave out anything a quote doesn’t include.

These numbers describe the swap when it was quoted. What the solver commits to is the amount, not the fee breakdown.

How prices are set

Cross-chain swaps: solvers compete for every quote, and the best price wins. The winning solver reports the fees. If its fees don’t add up to within a cent, Tern leaves the breakdown out and shows only the amounts.
Same-chain swaps: Tern asks DEX aggregators for routes and picks the best. The dollar values come from the aggregators’ own pricing.
Private swaps: priced like same-chain swaps, with privacy in place of network.

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Concepts

Guides

Protocol

Fees and pricing

Fee types

Other numbers in a quote

An example

What to show your users

How prices are set

​Fee types

​Other numbers in a quote

​An example

​What to show your users

​How prices are set

Fee types

Other numbers in a quote

An example

What to show your users

How prices are set