Quick Answer
Use webhooks when the data source can push events — they're lower latency and far cheaper at scale. Use polling when the source doesn't support webhooks, when you need to control timing exactly, or when event volume is unpredictable.
Webhooks vs Polling — Complete Comparison
A practical breakdown of when to use event-driven webhooks versus request-based polling — covering latency, cost, complexity, and reliability trade-offs.
At a Glance
| Dimension | Webhooks | Polling |
|---|---|---|
| Latency | Near-instant (milliseconds) | Up to poll interval (seconds–minutes) |
| Server Load | Low — only fires on events | High at scale — constant requests |
| Implementation Complexity | Medium — need public endpoint, signature verification | Low — simple GET loop |
| Reliability | Depends on source retry logic | You control retry / backoff |
| Cost at Scale | Low — proportional to events | High — proportional to interval × resources |
| Best Use Case | Payment events, git hooks, order notifications | Legacy APIs, batch jobs, unreliable sources |
How Webhooks Work
Webhooks are event-driven HTTP callbacks. When an event occurs on the source system — a payment succeeds, a pull request is merged, an order is placed — the source makes an HTTP POST request to a URL you've registered. Your server receives the payload and responds with a 2xx to acknowledge delivery.
The fundamental model is "don't call us, we'll call you." Your server only wakes up when there's something to process, which makes webhooks highly efficient at scale. The trade-off is that you need a publicly accessible HTTPS endpoint and you're trusting the source to deliver reliably.
How Polling Works
Polling is a pull model: your server periodically calls the source API on a fixed schedule — every 30 seconds, every minute, every hour — and checks whether anything has changed since the last call. If there are new items, you process them; if not, you discard the response and wait for the next interval.
Polling is simpler to implement and easier to reason about. You control the timing, the retry logic, and the error handling. But at scale, you're making API requests constantly regardless of whether there's anything to process, which burns through rate limits and API quota quickly.
When to Use Webhooks
- ✓The event source supports webhooks (Stripe, GitHub, Shopify, Slack all do).
- ✓You need near-real-time latency — payment confirmations, order processing, CI/CD triggers.
- ✓Event volume is predictable and tied to real activity (not artificially high).
- ✓You want to minimize API rate limit consumption on the source side.
- ✓Multiple downstream systems need the same event (fan-out via forwarding rules).
When to Use Polling
- →The source API doesn't support webhooks — many legacy enterprise APIs fall into this category.
- →You need deterministic timing — batch jobs that must run at a fixed schedule regardless of events.
- →The event source is unreliable and you can't trust its delivery guarantees.
- →Your receiving server isn't always publicly accessible (behind a firewall, on-premises).
- →You need to query for state rather than receive events (e.g., "what's the current inventory level?").
Hybrid Approaches
For production systems, many teams combine both approaches for resilience. Webhooks handle the real-time path; polling acts as a safety net to catch missed deliveries.
A common pattern: receive a webhook event, update your local state, but also run a nightly reconciliation job that polls the source API and fills any gaps. This is how Stripe recommends building reliable payment integrations — webhook for speed, polling for correctness.
Another pattern is webhook-triggered polling: a webhook arrives and triggers a short burst of polling to fetch full details (since webhooks often contain minimal data with an ID to look up).
Related Resources
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