World Chain Paymaster Preflight

Browser-only helper. It can (1) ping JSON-RPC (chainId/gasPrice), (2) ping a sponsor endpoint (optional), and (3) generate copyable curl templates. Settings are stored in localStorage.

Config

JSON-RPC URL (optional)

If CORS blocks, use a proxy or test from a backend/worker.

Sponsor / Paymaster Endpoint (optional)

Any POST endpoint that accepts JSON. This page won’t assume a specific schema.

App / Project ID (optional)

Note (optional)

Preflight

Try JSON-RPC calls and/or sponsor POST.

Checklist (quick)