CheckDigit

Offline check-digit validation for IBAN, BIC, EU VAT, GTIN/EAN/UPC and ISBN. Format check only.

Live service

• Web app and API: https://checkdigit.mike-tusa.workers.dev/

• Pricing: https://checkdigit.mike-tusa.workers.dev/docs

• Support: digitalpromohub.support@gmail.com

Related MCP server: Qiniso

Use it from an AI assistant (MCP)

CheckDigit is a remote MCP server (Streamable HTTP) at https://checkdigit.mike-tusa.workers.dev/mcp. Tools: validate_code, get_meta.

Cursor and Windsurf accept this config:

{
  "mcpServers": {
    "checkdigit": {
      "type": "http",
      "url": "https://checkdigit.mike-tusa.workers.dev/mcp"
    }
  }
}

Cline (MCP Servers > Remote Servers, or cline_mcp_settings.json) needs "type": "streamableHttp":

{
  "mcpServers": {
    "checkdigit": {
      "type": "streamableHttp",
      "url": "https://checkdigit.mike-tusa.workers.dev/mcp"
    }
  }
}

Claude Desktop: open Settings > Connectors, choose "Add custom connector" and paste https://checkdigit.mike-tusa.workers.dev/mcp. Or, for clients that only support local (stdio) servers, use the mcp-remote bridge: npx mcp-remote https://checkdigit.mike-tusa.workers.dev/mcp.

VS Code uses a servers key instead of mcpServers.

The server.json file is the MCP Registry manifest for this server.

Run your own copy

Requires Node.js 22+ and a Cloudflare account.

npm install
npx wrangler@4 dev      # local dev server

wrangler.toml is a template: create your own KV namespaces / D1 databases / rate-limit namespaces and replace the <PLACEHOLDER> values before npx wrangler@4 deploy. Any secrets the Worker reads go in wrangler secret put (or .dev.vars locally), never in the repo.

License

MIT (c) Digital Promo Hub. See LICENSE.