Definition
ESP rate limiting caps how many messages you can send per second or hour, protecting both your reputation and recipient infrastructure.
Honour the limits and implement backoff for over-limit responses.
ESP rate limits protect your reputation and recipient infrastructure, so honouring them matters. Backoff and retry handle over-limit responses gracefully. Pacing large sends keeps throughput within safe bounds.
Working Within Limits
Fetch and honour the provider rate-limit headers.
Implement backoff and retry for rate-limit responses.
Why It Matters
ESP rate limits protect your reputation and recipient infrastructure. Understanding them prevents throttling that delays sends.
Best Practices
- Fetch and honour the provider rate-limit headers.
- Implement backoff and retry for rate-limit responses.
- Do not configure limits higher than the IP can sustain.
- Pace large sends.
- Monitor throughput and errors.
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Frequently Asked Questions
A maximum throughput, for example messages per second or hour. ESP rate limits protect your reputation and recipient infrastructure, so honouring them matters.
Often yes, with approval as reputation improves. Backoff and retry handle over-limit responses gracefully.
Requests return errors and queue locally. Pacing large sends keeps throughput within safe bounds.
To protect reputation and recipient infrastructure. ESP rate limits protect your reputation and recipient infrastructure, so honouring them matters.
Back off and retry. Backoff and retry handle over-limit responses gracefully.