Don't see your question here?

This page contains general checkout questions. Each page in the docs contains context-specific FAQs.

If your question still isn't answered, please reach out to us on Discord.


How much does Paper cost?

There is no cost to sellers! Buyers pay a 1% service fee on top of payment processing fees. See Pricing for more details.

How long does implementation take?

A full-featured checkout link takes minutes to set up:

  1. Register your contract.
  2. Create a 🔗 Shareable Checkout Link.
  3. Send users to that link. Done ✨!

When you're ready to customize further, you can tinker with styling, SDKs, webhooks, dynamic pricing, and more.

Smart contract support

Which blockchains and currencies are supported?

BlockchainSupported Currencies
EthereumETH, USDC
OptimismETH, USDC

Is my smart contract supported?

BlockchainContract Types
Your custom contract
thirdweb contracts and contracts built from thirdweb base contracts
SolanaCandy Machine v2
Auction House

Are marketplace contracts supported?

Yes! See Marketplace Sales for more details.

We also support thirdweb Marketplace (EVM) and Auction House (Solana) contracts.

Can I sell an NFT that is already minted?

Yes! You'll need to "wrap" your NFT with a marketplace contract like thirdweb marketplace or build your own. This "direct listing" approach works like this:

  • The seller has an NFT already minted and wants to sell it.
  • The seller approves the marketplace contract to take this NFT from their wallet once a buyer offers a specified amount. The NFT is not moved until a sale is completed.
  • A buyer agrees to pay the specified amount. They pay via your Paper checkout flow.
  • After the buyer's payment is successful, Paper calls the "buy" method with the expected amount in crypto to the marketplace contract. This method transfers the NFT to the buyer's wallet.


What regions does Paper support credit card payments?

Paper uses multiple payment processors and supports credit card payments in most countries and all 50 US states. Select countries that the US cannot conduct business with are not supported.

What fiat payment options are accepted?

Paper accepts: credit/debit cards (Visa, Mastercard, American Express, Discover, UnionPay, JCB, Diners Club), Apple Pay, Google Pay, iDEAL

What is the price limit for checkouts?

Paper limits checkouts to be priced at $2,000 USD and reserves the right to change this limit based on your checkout's risk profile.

If you need a higher price limit, please contact sales.

When does Paper require identity verification (KYC)?

Paper combines buyer, merchant, payment method, device, and behavioral signals from multiple vendors to compute the riskiness of a purchase. A small portion of buyers (< 3% and varies by merchant) will be prompted to submit a photo ID and take a webcam selfie. This step is automated and takes under 1 minute.

Reminder: Paper takes on all chargeback liability from the developer!


Is there a test credit card?

Yes, please use the following card numbers. The expiry date, CVV, and postal code do not matter.

Card NumberDescription
4242424242424242A "low risk" card.
4000000000009235A "high risk" card that prompts KYC.

Where can I get testnet funds?

Here are faucets to receive testnet funds:

ChainCurrencyFaucet link
Mumbai (Polygon)MATICFaucet
Goerli (Ethereum)ETHFaucet
Sepolia (Etereum)ETHFaucet
Goerli (Optimism)ETHFaucet


Can I customize the checkout to match my branding?

Yes, customize colors and UI elements to fit your theme for Shareable Checkout Links. Or embed Checkout Elements in your app with granular control of colors.

How do allow my users to redeem utility with their NFT?

NFTs are a great way to gate content! Once the NFT is purchased, you can provide a link to redeem their utility on the post-purchase page and email.

Listen to webhooks to update your database or send a custom email when the NFT has been transferred.

How do I customize the emails sent to buyers?

See Advanced Customizations for more customization of the email after a buyer completes their purchase.

Are checkouts translated into different languages?

Yes, the checkout is localized to the buyer's browser language, or you can force a specific language. See Translations for more details.


What if my users don't have a wallet?

Buyers who don't have a wallet can create one with their email or social login. This uses our non-custodial Embedded Wallet product.

How does my user transfer the NFT from the Embedded Wallet?

Buyers can visit My Wallets to view and transfer NFTs in their Embedded Wallets.

This page does not support transfers for self-custody wallets like MetaMask.