Free browser tool - Updated 2026-07-06
402 Response Builder
Build an x402 v2 402 response from price, network, scheme, recipient, asset, and resource fields. The tool keeps everything in your browser and emits copyable HTTP and JSON examples.
PAYMENT-REQUIRED header
402 response example
Decoded JSON and retry curl
Retry shape
What this output means
The generated response is a documentation and test fixture for the v2 shape. It advertises a paid resource, an accepted payment option, and a Base64 JSON header value. A real client must still create the scheme-specific signed payment payload before retrying with PAYMENT-SIGNATURE.
For EVM and Solana USDC defaults, the tool converts dollars to atomic units with six decimals. If you use a custom asset with different decimals, adjust the amount in your production SDK or middleware configuration.
How to use it
- Enter the protected resource URL and a short resource description.
- Choose the payment scheme and CAIP-2 network identifier.
- Confirm or replace the default asset and seller recipient address.
- Copy the generated PAYMENT-REQUIRED header, JSON object, or curl retry shape.
FAQ
Is this a live x402 server?
No. It is a client-side generator for example 402 responses and headers. A production server still needs real x402 middleware, verification, settlement, logging, and error handling.
Why does the tool output amount instead of price?
Seller route configuration can use dollar strings, but the PaymentRequired object advertises token amounts in atomic units plus an asset identifier. For USDC, six decimals means $0.01 becomes 10000.
Can I use the curl command to pay?
The curl command shows the retry shape. A real PAYMENT-SIGNATURE value must come from an x402 v2 client that parsed the requirements and signed a scheme-specific payload.