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Signature Verification

Verify payment and API signatures. Compare computed HMAC/RSA signatures with received values. Supports MD5, SHA1, SHA256, SHA512, RSA-SHA256.

HMAC
RSA
Enter message, key, and received signature to verify
Common Payment Signature Rules

Alipay: Sort params by key, concatenate with &, append key, then sign with MD5 or RSA2 (SHA256).

WeChat Pay: Sort params by ASCII, concatenate with &key=, then sign with HMAC-SHA256 or MD5.

Stripe: Use HMAC-SHA256 with the signing secret. Compare using timing-safe equals.

Tip: Paste the raw parameter string (before signing) as the message. The signature should be computed on exactly this string.

How to use this tool

Compare a computed payment or API signature with a received value during an authorized integration test.

Suggested workflow

  1. Recreate the exact signed payload and algorithm.
  2. Use a test key from your sandbox environment.
  3. Compare the calculated signature with the received signature.

Good to know

Only test services and credentials you own or are explicitly authorized to use.

Signature Verification - CodeTools Toolbox - 47 free online developer tools.