How to Mint Tokens in a Single API Call (NFTs)

Unique Assets (ERC-721)
Editions (ERC-1155)
Compressed NFTs
Non-transferrable NFTs

To mint and airdrop unique digital assets, you can follow the guide on the Quickstart. For more detail, please check the API reference. You can watch a quick video tutorial for this here.

SFTs (semifungible tokens) follow the ERC-1155 standard. Each token is a replica of a predefined template. Each collection (smart contract) can contain multiple templates, which can contain many tokens.To get started, it’s recommended to read the Introduction for general information on how the minting product works.

This API only supports EVM chains self-serve. Contact us if you need support for another chain.

1. Create an SFT collection to hold your templates

cURL

  curl --request POST \
    --url https://staging.crossmint.com/api/2022-06-09/collections \
    --header 'accept: application/json' \
    --header 'content-type: application/json' \
    --header 'x-api-key: YOUR_API_KEY' \
    --data '
{
    "chain": "polygon-amoy",
    "fungibility": "semi-fungible",
    "metadata": {
      "name": "My New Collection",
      "imageUrl": "https://www.crossmint.com/assets/crossmint/logo.png",
      "description": "A new collection with its own dedicated smart contract"
    }
}'

See example response

JSON

  {
    "id": "5263650e-6d43-4ed3-9e31-0cf593d076a4",
    "metadata": {
      "name": "Test Collection",
      "description": "Test",
      "imageUrl": "https://cdn.io/metadata.json",
      "symbol": "XMINT"
    },
    "fungibility": "semi-fungible",
    "onChain": {
      "chain": "polygon-amoy",
      "type": "erc-1155"
    },
    "actionId": "5263650e-6d43-4ed3-9e31-0cf593d076a4"
  }

2. Create a template within that collection

cURL

curl --request POST \
  --url https://staging.crossmint.com/api/2022-06-09/collections/{collectionId}/templates \
  --header 'accept: application/json' \
  --header 'content-type: application/json' \
  --header 'x-api-key: YOUR_API_KEY' \
  --data '
  {
    "onChain": {
      "tokenId": "2"
    },
    "supply": {
      "limit": 10
    },
    "metadata": {
      "name": "My template",
      "image": "https://www.crossmint.com/assets/crossmint/logo.png",
      "description": "A new token template for my ERC1155 collection"
    }
  }'

See example response

JSON

{
  "templateId": "58b0c1aa-e457-48dd-bb55-5a27e6a92f74",
  "metadata": {
    "name": "My template",
    "image": "ipfs://bafkreigbqsmxzkbjgbwtj6exfdt5z3t3swgoysf7hr6vjzddqnmykj6x2u",
    "description": "A new token template for my ERC1155 collection"
  },
  "onChain": {
    "tokenId": "1"
  },
  "supply": {
    "limit": "10",
    "minted": "0"
  }
}

3. Mint an SFT from a template

Mint SFTs from the template and send them to wallets or email addresses.

cURL

  curl --request POST \
    --url https://staging.crossmint.com/api/2022-06-09/collections/{collectionId}/sfts \
    --header 'accept: application/json' \
    --header 'content-type: application/json' \
    --header 'x-api-key: YOUR_API_KEY' \
    --data '
    {
      "templateId": "58b0c1aa-e457-48dd-bb55-5a27e6a92f74",
      "recipient": "email:user@example.com:polygon-amoy",
      "amount": 1
    }'

See example response

JSON

{
  "actionId": "a91c15e3-60f2-4a45-bf1a-cee508981667",
  "action": "nfts.create",
  "status": "pending",
  "data":
  {
    "chain": "polygon-amoy",
    "collection":
    {
      "id": "84e3d617-9c1b-4e7a-9686-522a9ea7c520",
      "contractAddress": "0x9b8ab8949bd7E73E61945b88F7fe12151f98ad3C"
    },
    "recipient":
    {
      "walletAddress": "0xcFDc00Cf926A5053f9Cdf004e6DF17e6dEB2E146",
      "email": "testy@crossmint.com"
    },
    "token":
    {
      "id": "a91c15e3-60f2-4a45-bf1a-cee508981667"
    }
  },
  "startedAt": "2024-01-02T22:05:01.000Z",
  "resource": "https://staging.crossmint.com/api/2022-06-09/actions/a91c15e3-60f2-4a45-bf1a-cee508981667"
}

All set!To confirm delivery, use the transaction status API or set up a webhook.

What are Compressed NFTs?

Compressed NFTs are a new standard on the Solana blockchain, for minting NFTs with the lowest cost amongst L1 and L2 blockchains, and the highest throughput (thousands of NFTs per second). Read more details about how it works here.Using this standard to mint NFTs is extremely complicated if you manage everything on your own. On top of the intrinsic complexity usually required to mint a regular NFT, compressed NFTs require deploying and managing Merkle trees, batching, and dealing with nascent infrastructure. Crossmint also supports updating the NFT metadata after minting. Please refer to this doc page.Here’s where Crossmint can help: we’ve done all the hard work so that minting compressed NFTs is no harder than minting regular ones: all it takes is a single API call, and you can even use one of Crossmint’s no-code tools to do so.

Current Protocol Limitations

There’s a 10-30 second delay between when an NFT is minted and it shows in wallets.

How to use the Minting API with Compressed NFTs

The Minting API for Compressed NFTs is exactly the same as for regular NFTs, but it only works on the Solana blockchain.POST https://staging.crossmint.com/api/2022-06-09/collections/<collection-id>/nfts

You can mint both compressed and non-compressed NFTs on the same collection.

cURL

curl --request POST \
  --url https://staging.crossmint.com/api/2022-06-09/collections/default-solana/nfts \
  --header 'Content-Type: application/json' \
  --header 'X-API-KEY: <x-api-key>' \
  --data '{
    "recipient": "email:john.doe@example.com:solana",
    "metadata": {
      "name": "Crossmint Example NFT",
      "image": "https://www.crossmint.com/assets/crossmint/logo.png",
      "description": "My NFT created via the mint API!"
    },
    "compressed": true,
    "reuploadLinkedFiles": false
  }'

The above will return an NFT ID. Use it in the next call to retrieve the mint status.

cURL

curl --request GET \
  --url https://staging.crossmint.com/api/2022-06-09/collections/{collectionId}/nfts/{nftId} \
  --header 'X-API-KEY: X_API_KEY'

Be sure to replace:

X_API_KEY, {collectionId} and {nftId}
Recipient: change VALID_WALLET_ADDRESS with the wallet you want to send the NFT to
Metadata: add the name, image, and description.

To explore compressed NFTs on the blockchain, you must use Orb, powered by Helius

Other explorers, like Solscan, still have not added support.

There are two ways to set the transferrability of NFTs:

Defining it at the smart contract level
If you are using custodial wallets, enabling or disabling transfers from the frontend

If you want to configure it at the smart contract level, see the following endpoints:

Endpoint	Chain	Description
Set Transferability	EVM and Aptos	Set transferability to on or off
Get Transferability	EVM and Aptos	Get transferability configuration

For Solana or other non-EVM chain support, contact us

The API also has an idempotent version which prevents you from calling the same API action multiple times and mitigates the risk of unwanted NFT duplicates.

Introduction

Tokens (NFTs, SFTs)

Verifiable Credentials (VCs)

API Reference

Mint Tokens

1. Create an SFT collection to hold your templates

2. Create a template within that collection

3. Mint an SFT from a template

What are Compressed NFTs?

Current Protocol Limitations

How to use the Minting API with Compressed NFTs

To explore compressed NFTs on the blockchain, you must use Orb, powered by Helius

Advanced Guides

Dynamic NFTs

List for Sale

Webhooks & Status APIs

Bring your own Contract