CheckAPI C# SDK

Official C# SDK for CheckAPI — Ukrainian bank receipt verification API.

Upload a photo of a bank receipt, and get an instant Verified: true/false with the detected amount and card number — in about 1 second.

Supported banks: PrivatBank, monobank, OTP Bank, A-Bank, Raiffeisen.

Installation

dotnet add package CheckApi

Or add to your .csproj:

<PackageReference Include="CheckApi" Version="1.0.0" />

Zero external dependencies — uses built-in System.Net.Http and System.Text.Json (.NET 6+).

Quick start

using CheckApi;

var client = new CheckApiClient("YOUR_API_KEY");

var result = await client.VerifyAsync(
    "receipt.jpg",
    expectedAmount: 2450.00m,
    expectedCardLast4: "7731"
);

Console.WriteLine(result.Verified);   // True
Console.WriteLine(result.Reason);     // "confirmed"
Console.WriteLine(result.DurationMs); // 870

How it works

1. You send a receipt photo + expected amount + last 4 digits of the recipient's card
2. CheckAPI verifies the receipt and returns the result in ~1 second
3. Verified: true means the amount and card match; false comes with a Reason code

Pricing

Plan	Price	Checks	Per check
Start	$30	1,000	$0.03
Business	$200	10,000	$0.02
Custom	$500+	custom	custom

Pay in USDT or by invoice. No subscription.

Links

• Website: check.sarmkadan.com
• API docs: check.sarmkadan.com/docs
• Live demo: check.sarmkadan.com/#demo
• Contact: Telegram @sarmkadan

License

MIT