Register your CryptoNow account.

Open Dashboard and add a merchant.

• Name - your site / store name.
• Webhook URL - server-to-server notifications about payment events come here. If you do not set it, check payment status through View Session.
• Default return URL - your store, where the customer can return.
• Solana Wallet - the wallet where payments go by default.
• Commission mode - the fee is either added to the payment amount or deducted from it (Read here).
• Session timers - configure timing for sessions (Read here).

Payments go directly to your wallet, so we recommend a non-custodial Solana wallet: Solflare, Trust Wallet, MetaMask.

Use a wallet with Solana support.

After you create a merchant, you will see a public key and a private key in Dashboard. Public key identifies your merchant. Private key signs API requests.

// Keep the API private key and seed phrase in a safe place and protect them carefully.

• Merchant - your store created in Dashboard. It stores your wallet address, other data, API keys, and the history of payments and sessions.
• Merchant Edit - If you edit any parameters such as wallet, webhook URL, Default return URL, commission mode, or Session timers in your merchant, the changes apply only to new sessions. Existing sessions keep the data that was saved when the session was created.
• Customer - The person who pays for your product or service.
• Session link (payment link) - you receive it when the session is created and direct the customer to it. When they open "url", they can pay.
• Fee - each payment is split into "merchant_receives" (your net amount) and "fee" (CryptoNow commission). For payments from $0.10 to $1.99 the fee is always $0.01. From $2.00 and above it increases by $0.01 per whole dollar.
  Example:
  $0.10 -> $0.01

  $1.99 -> $0.01

  $2.00 -> $0.02

  $10.00 -> $0.10

  $100.00 -> $1.00
• Commission mode - you choose whether the service fee is paid by Merchant or by Customer. If set to Merchant, the customer pays the exact "amount" you passed, and you receive "amount - fee" to your wallet. If set to Customer, the fee is added on top, the customer pays "amount + fee" and you receive the exact "amount" to your wallet. The final amount the customer pays is "total_amount".
• For USDC, the amount stays the same - 1:1 equivalent to USD. If the customer pays in SOL, the SOL amount is calculated at our rate, locked once when the customer moves to the payment step and stays unchanged for the rest of that session.

• You can create a payment with an amount from $0.10 to $100,000.
• Max merchants per user: 20.
• Merchant API v1 rate limit: 500 requests per minute, plus a short burst limit of 200 requests per 10 seconds.

You can activate or deactivate merchant in the Dashboard. Deactivating a merchant blocks API requests, dashboard session creation, and merchant edits. You can turn it back on again at any time.

Content-Type: application/json.

Use UTF-8 for the JSON body.

POST is signed with the request body (payload). GET is signed with params and query.

Each response returns a status flag and the result data.

• success - true or false.
• data - the result of the request.
• error - message when success is false.
• signature - response signature for { success, data }.

Successful request:

{
  "success": true,
  "data": {
    "property": "value",
    "second_property": "second_value"
  },
  "signature": "b8e4c0d13f6a9b27d5e8f104c3a6d92b7e0f5a1c8d4b63f290a7e5c1d8b4f603"
}

Request with an error:

{
  "success": false,
  "error": "error message"
}

• X-Public-Key - identifies your merchant and matches the public key shown in the Dashboard.
• X-Signature - HMAC SHA-256 signature of the request payload signed with your private key from Dashboard.

1. Build the payload from the request data.
2. Generate an HMAC SHA-256 signature using your private key and the canonicalization rules.
3. Send the signature in X-Signature together with X-Public-Key.

How to generate the signature (Read Here).

• 401 - Authentication failed.
• 429 - Too many requests (rate limit exceeded).
• 500 - Internal server error.

Build the canonical payload this way:

1. Sort object keys alphabetically at every level.
2. Remove fields with undefined values. Do not remove fields whose value is null.
3. Keep the original order of items inside arrays.
4. Serialize the result to one exact JSON string before signing.
5. Use that final JSON string for HMAC SHA-256.

It makes sure you and CryptoNow always sign the same JSON string. Without canonicalization, the same payload could produce a different signature just because keys were written in a different order.

For POST requests, sign the JSON from the request body. For GET requests, sign the JSON object built from params and query.

Use one of the examples below to create signatures for Create Payment requests.

• Request #1: immediately after the event.
• Request #2: 5 seconds after the previous attempt.
• Request #3: 10 seconds after the previous attempt.
• Request #4: 30 seconds after the previous attempt.
• Request #5: 2 minutes after the previous attempt.
• Request #6: 10 minutes after the previous attempt.
• Request #7: 1 hour after the previous attempt.
• Request #8: 6 hours after the previous attempt.
• Request #9: 24 hours after the previous attempt.

1. order_id must be unique per merchant.
2. success_url and return_url can be HTTP or HTTPS.

• "return_url" is used for the Back button, so the customer can return to your store at any point during payment. On small screens the button is hidden. If it is not passed, we use Default return URL from merchant settings.
• After a successful payment, the customer can click "Get your service" to access the service they paid for. The button uses "success_url" if provided, otherwise "return_url", otherwise the default return URL. If none are set, the button is disabled.
• "recipient_wallet" replaces the recipient wallet for this payment, and funds go to the wallet set in "recipient_wallet".

curl 'https://cryptnow.io/api/v1/payment/create' \
  -X POST \
  -H 'X-Public-Key: public_4F8x...' \
  -H 'X-Signature: 21bc4f0d2d0e...' \
  -H 'Content-Type: application/json' \
  -d '{
    "amount": "14.20",
    "currency": "USD",
    "order_id": "147",
    "success_url": "https://site.io/order/5f2c9b"
  }'

{
  "success": true,
  "data": {
    "payment_id": 456,
    "session_key": "f3a91c20-7d44-4b8f-9c2a-6e15d3b8a904",
    "session_status": "pending",
    "order_id": "147",
    "amount": "14.20",
    "total_amount": "14.20",
    "merchant_receives": "14.06",
    "fee": "0.14",
    "currency": "USD",
    "payment_method": "ALL",
    "token": null,
    "network": "Solana",
    "payment_status": null,
    "recipient_wallet": "BQLxH3Drh51hbjfR9GMeB5FTBZyCtpYLvD5eqpfXupyo",
    "payer_wallet": null,
    "txid": null,
    "created_at": "2026-02-14T10:00:00Z",
    "active_at": null,
    "paid_at": null,
    "inactive_at": "2026-02-14T10:30:00Z",
    "url": "https://cryptnow.io/payment?session=f3a91c20-7d44-4b8f-9c2a-6e15d3b8a904",
    "return_url": null,
    "success_url": "https://site.io/order/5f2c9b"
  },
  "signature": "b8e4c0d13f6a9b27d5e8f104c3a6d92b7e0f5a1c8d4b63f290a7e5c1d8b4f603"
}

{
  "success": false,
  "error": "Payment with this order_id already exists"
}

• 400 - Invalid request, validation error, or unknown field(s).
• 401 - Authentication failed.
• 404 - Merchant not found.
• 409 - Duplicate order_id or payment already exists.
• 429 - Too many requests (rate limit exceeded).
• 500 - Internal server error.

{
  "success": true,
  "data": {
    "payment_id": 456,
    "session_key": "f3a91c20-7d44-4b8f-9c2a-6e15d3b8a904",
    "session_status": "pending",
    "order_id": "147",
    "amount": "14.20",
    "total_amount": "14.20",
    "merchant_receives": "14.06",
    "fee": "0.14",
    "currency": "USD",
    "payment_method": "ALL",
    "token": null,
    "network": "Solana",
    "payment_status": null,
    "recipient_wallet": "BQLxH3Drh51hbjfR9GMeB5FTBZyCtpYLvD5eqpfXupyo",
    "payer_wallet": null,
    "txid": null,
    "created_at": "2026-02-14T10:00:00Z",
    "active_at": "2026-02-14T10:00:15Z",
    "paid_at": null,
    "inactive_at": "2026-02-14T10:30:00Z",
    "url": "https://cryptnow.io/payment?session=f3a91c20-7d44-4b8f-9c2a-6e15d3b8a904",
    "return_url": "https://site.io",
    "success_url": "https://site.io/order/5f2c9b"
  },
  "signature": "b8e4c0d13f6a9b27d5e8f104c3a6d92b7e0f5a1c8d4b63f290a7e5c1d8b4f603"
}

{
  "success": false,
  "error": "Session not found"
}

• 400 - Invalid session_key.
• 401 - Authentication failed.
• 404 - Session not found.
• 429 - Too many requests (rate limit exceeded).
• 500 - Internal server error.

1. date_from and date_to must be valid dates (DD.MM.YYYY or DD.MM.YYYY HH:MM[:SS]). Seconds are optional.
2. date_from must be earlier than date_to.
3. Filters are interpreted in UTC for both Dashboard CSV export and API export.

curl 'https://cryptnow.io/api/v1/payment/export' \
  -X POST \
  -H 'X-Public-Key: public_4F8x...' \
  -H 'X-Signature: 21bc4f0d2d0e...' \
  -H 'Content-Type: application/json' \
  -d '{
    "date_from": "10.01.2026 09:00",
    "date_to": "12.01.2026 18:30:45",
    "status": "all"
  }'

{
  "success": true,
  "data": [
    {
      "payment_id": 456,
      "session_key": "f3a91c20-7d44-4b8f-9c2a-6e15d3b8a904",
      "session_status": "inactive",
      "order_id": "147",
      "amount": "14.20",
      "total_amount": "14.20",
      "merchant_receives": "14.06",
      "fee": "0.14",
      "currency": "USD",
      "payment_method": "ALL",
      "token": "USDC",
      "network": "Solana",
      "payment_status": "paid",
      "recipient_wallet": "BQLxH3Drh51hbjfR9GMeB5FTBZyCtpYLvD5eqpfXupyo",
      "payer_wallet": "5eXgehWkldzarVA3LgJFkQkZbVF1eJHGxFKpNWrR7oaj",
      "txid": "WrHzgMNZERNUVc3ojR5Z199fPDxUVqTHAhrZvZFbcG7ajPVVhjG6spwKCPWXdy38J19fKSFFtP2gL87Jr9cmyLD",
      "created_at": "2026-02-14T10:00:00Z",
      "active_at": "2026-02-14T10:00:15Z",
      "paid_at": "2026-02-14T10:01:21Z",
      "inactive_at": "2026-02-14T10:30:00Z",
      "url": "https://cryptnow.io/payment?session=f3a91c20-7d44-4b8f-9c2a-6e15d3b8a904",
      "return_url": "https://site.io",
      "success_url": "https://site.io/order/5f2c9b"
    }
  ],
  "signature": "b8e4c0d13f6a9b27d5e8f104c3a6d92b7e0f5a1c8d4b63f290a7e5c1d8b4f603"
}

{
  "success": false,
  "error": "Invalid date_from format"
}

• 400 - Invalid filters, date format, or unknown field(s).
• 401 - Authentication failed.
• 429 - Too many requests (rate limit exceeded).
• 500 - Internal server error.