n8n Webhook: Retry HTTP with Exponential Backoff + DLQ

Reliable n8n Webhook delivery with automatic retries + dead-letter queue (DLQ)

This n8n workflow accepts an incoming JSON payload on an n8n Webhook, forwards it to your target HTTP endpoint, retries common transient failures using exponential backoff with jitter, and sends permanently failing payloads to a dead-letter queue webhook.

What this workflow does

• Receives the request: Listens for an incoming POST on an n8n Webhook endpoint and immediately returns n8n’s default acknowledgement (the caller is not informed whether delivery later succeeds).
• Captures payload + config: Reads configuration values such as the target URL, dead-letter queue URL, and retry limits, then stores the incoming request body as the payload.
• Forwards to your target: Sends the payload via HTTP POST to the configured target endpoint and treats any 2xx response as successful.
• Retries only retryable failures: Retries network errors (including timeouts) plus HTTP 408, 429, and 5xx. Any other non-2xx status is considered non-retryable.
• Exponential backoff + jitter: Uses a delay starting at 2 seconds by default, doubling per attempt, adding up to 25% jitter, and capping at 300 seconds. Default total attempts: 5.
• Dead-letter queue hand-off: After the last attempt—or on any non-retryable status—the workflow posts the payload and failure metadata (attempts, last status, error, reason) to the DLQ webhook. If the DLQ hand-off fails, the payload can be lost.

Use cases

• Improving delivery reliability for SaaS-to-SaaS webhook integrations in n8n.
• Handling rate limits (HTTP 429) and transient server issues (5xx) without manual intervention.
• Ensuring failed deliveries are tracked and replayed later via a DLQ webhook.

Technical details

• n8n nodes/workflow building blocks: Webhook, HTTP POST (HTTP request), if, set, code, wait.
• Designed for n8n workflow automation engineers and SaaS operators needing retry logic with exponential backoff and jitter.