Glossary

A reference of the terms used across the Exchange section (Swap, Buy, Sell, Earn, Card). Definitions match the vocabulary used in the Ledger device-side Exchange application and the partner-facing flow documentation.

Terms are listed alphabetically.

Account

A Ledger wallet address on a cryptocurrency network. A user can have several accounts on the same blockchain (for example several Ethereum addresses).

CAL: Crypto Asset List

The Ledger-maintained, HSM-signed list of currencies the device-side Exchange application can display. The CAL is what lets the device verify that the FROM and TO assets in a transaction proposal really are the assets the user expects.

Coin

The native currency on a blockchain. Identified with "type": "coin". For example, on Ethereum only ETH has type coin; everything else is a token.

Coin application

The Ledger device app that handles a specific blockchain (Bitcoin app, Ethereum app, …). The Exchange application drives two coin applications during a swap: one for the FROM asset and one for the TO asset.

[
  { "id": "ETH",  "type": "coin",  "blockchain": "ethereum", "chainId": 1 },
  {
    "id": "USDC",
    "type": "token",
    "blockchain": "ethereum",
    "chainId": 1,
    "contract": "0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48"
  }
]

Exchange application

The device-side application that orchestrates Swap and Sell. It receives the partner’s signed transaction proposal from Ledger Wallet, validates it against the CAL, drives the FROM and TO coin applications, and shows the final review screen to the user.

Fixed quote

A quote whose rate is guaranteed for a defined window (at least 60 seconds). The user receives exactly the amount displayed if they accept within that window. Compare with Floating quote.

Floating quote

A quote whose rate is not guaranteed. The user can receive less than the displayed amount according to market fluctuations, but is protected by a maximum slippage value defined by the partner. Compare with Fixed quote.

KYC: Know Your Customer

Identity-verification process some partners require before letting a user trade. See Registration policy.

Ledger fee

Fee taken by Ledger as part of a swap. Subtracted from the partner’s swap rate output when computing the receiving amount.

LiveApp

A third-party application that runs inside Ledger Wallet through the dApp browser or the Wallet API. Each Exchange flow (Swap, Buy, Sell, Earn, Card) is implemented by one or more partner LiveApps.

Partner

A third-party service integrated with Ledger Wallet to provide a Buy, Sell, Swap, Earn, or Card flow. In the Exchange application’s vocabulary, also called the Trade Partner.

Partner fee

Fee taken by the partner as part of a swap. Subtracted from the partner’s swap rate output when computing the receiving amount.

`payinNetworkFees`

The network (gas) fee paid by the user to send the FROM crypto from their Ledger account to the partner. Not included in the receiving amount displayed in the quote, but shown separately above it.

Provider

Synonym for partner used in the Buy / Sell / Card flows (providers-backend.mdx, providers-liveapp.mdx).

Quote

A trade offer returned by a partner for a given input amount and currency pair. Includes the receiving amount, exchange rate, fee breakdown, and whether the rate is fixed or floating. The Exchange flow is built around displaying and accepting quotes.

Receiving amount

The amount the user will receive in the TO currency, after all fees are applied. Computed as:

receivingAmount = swapRateOutput × (1 − ledgerFee − partnerFee) − withdrawalFee

payinNetworkFees are not included.

Registration policy

Whether a partner requires the user to register / complete KYC before trading. Displayed on each quote card as Needed or Not needed.

Signed transaction proposal

A transaction proposal sent by the trade partner, signed with the partner’s private key. Ledger Wallet forwards it to the Exchange application, which verifies the signature against the partner’s public key registered with Ledger.

Slippage

The maximum acceptable difference between the quoted rate and the executed rate on a floating quote. Set by the partner and surfaced to the user.

Swap rate output

The rate provided by the partner for a swap, before any fee deduction. The receiving amount is derived from it.

Token

A non-native asset on a blockchain. Identified with "type": "token" and a contract field. For example, USDC on Ethereum:

{
  "id": "USDC",
  "type": "token",
  "blockchain": "ethereum",
  "chainId": 1,
  "contract": "0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48"
}

Trade Partner

The actor that proposes a trade offer to the Ledger Wallet user. Equivalent to partner / provider. The partner’s offer must be displayed faithfully on the device screen by the Exchange application.

Withdrawal fee

Fee paid by the user to cover the gas needed to move the TO crypto from the partner’s wallet back to the user. Subtracted when computing the receiving amount.