How to Test USDT & USDC Payments on Ethereum Sepolia

Network Details

Network

Ethereum Sepolia

Recommended Wallet

Rabby

Gas Token

ETH

Token Standard

ERC-20

Chain ID

11155111

Useful Resources

Step 1 — Configure Your Wallet

Install Rabby, create a dedicated test account, and select the Ethereum Sepolia test network. Verify the network configuration before submitting any transaction.

Step 2 — Obtain Test Tokens

Request some test ETH to cover blockchain transaction fees. You will also need test USDT or USDC tokens supported by the crptoX Sandbox.

Use the network faucet to obtain test ETH. Gas tokens and test stablecoins are separate assets. Make sure you also hold the supported test token before attempting a transfer.

Step 3 — Create a Sandbox Invoice

Create an invoice using your Sandbox API secret. The response includes the payment address and the amount to transfer.

curl -X POST https://crptox.com/api/v1/invoices \
  -H "Authorization: Bearer YOUR_SANDBOX_API_SECRET" \
  -H "Content-Type: application/json" \
  -H "Accept: application/json" \
  -H "Idempotency-Key: sandbox-test-1001" \
  -d '{
    "network": "ethereum",
    "asset": "usdt",
    "amount": "1.000000",
    "description": "Sandbox test payment"
  }'

This request is an example. Use a valid amount accepted by your API configuration. The payment address must be taken from the actual API response.

Step 4 — Send the Test Payment

For EVM testnets, you can submit a token transfer directly through the blockchain explorer using the verified token contract and your Rabby wallet.

1. Open the testnet blockchain explorer.
2. Open the supported USDT or USDC token contract using the View on Explorer link provided above.
3. Open the Contract section and select Write Contract or Write as Proxy, when applicable.
4. Connect your Rabby wallet and verify the selected test network.
5. Call transfer(address,uint256) using the invoice payment address and the amount converted to token base units.
6. Review the transaction, confirm it in Rabby, and save the transaction hash.

transfer(address to, uint256 amount)

1 token (6 decimals)  = 1000000
1 token (18 decimals) = 1000000000000000000

Step 5 — Verify the Payment

After submitting the transfer, inspect the transaction in the blockchain explorer and check how crptoX processes the payment.

1. Open the transaction hash in the testnet explorer.
2. Verify that the transaction succeeded.
3. Confirm the recipient, token contract, and transferred amount.
4. Check the invoice and payment status in crptoX after the required confirmations.
5. Verify that your application received and processed the expected webhook.