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Returns the minimum and maximum for a card payment in a given fiat currency and crypto asset. Validate the amount against these before quoting - an amount outside the window fails at purchase with a worse user experience than a disabled button.

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Request

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string
required
ISO 4217 code of the currency the card is charged in, e.g. EUR.
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string
required
The asset the purchase settles as, e.g. USDC.

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Response

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string
Echo of the fiat currency.
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string
Echo of the crypto asset.
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string
The smallest chargeable amount, as a decimal string in the fiat currency’s major unit.
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string
The largest chargeable amount, as a decimal string in the fiat currency’s major unit.
These are the rail’s limits per payment. A buyer’s own ceiling can be lower - it depends on their verification tier with the card partner - so a payment inside this window can still be declined for that buyer.
The window moves with the currency, and not proportionally: EUR runs 25 to 15,000 while GBP runs 21.42 to 12,847.83. Read the endpoint for the pair you are charging rather than converting one currency’s window into another.

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Errors