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Datetime format validation for webhook timestamps

Webhook signatures often include a timestamp header; skew between client and server can cause rejections. ISO-8601 strings differ from Unix seconds. Align parsing and tolerance with your provider docs.

Common causes

  • Clock skew beyond allowed window.
  • Seconds vs milliseconds confusion.
  • Wrong timezone in string format.

How to fix

  • Use Timestamp Validator to compare now vs header.
  • Sync NTP on servers.
  • Configure tolerance to match Stripe/GitHub-style rules.

Use our tool

Validate timestamp