​
Rate Limiting Overview

Shoutbox implements rate limiting for both API and SMTP email sending to ensure platform stability and maintain high deliverability rates. These limits are based on your subscription tier and are enforced across different time intervals.

​
Time-based Limits

Rate limits are enforced across multiple time windows:

  • Per Minute: Controls burst sending rates
  • Per Hour: Manages medium-term sending volume
  • Per Day: Regulates daily email throughput
  • Per Month: Sets overall monthly sending capacity

​
Subscription-based Limits

Your specific rate limits are determined by your subscription tier. To view your current limits:

  1. Log into your Shoutbox dashboard
  2. Navigate to Settings → Subscription
  3. Check the “Rate Limits” section

​
Handling Rate Limits

​
API Rate Limiting

When you exceed your rate limit via API, you’ll receive a 429 Too Many Requests response with a JSON body:

{
  "error": "rate_limit_exceeded",
  "message": "Rate limit exceeded. Please check your subscription limits or contact support for increased limits.",
  "reset_at": "2024-01-01T00:00:00Z"
}

​
SMTP Rate Limiting

For SMTP connections, exceeding rate limits will result in temporary failures with appropriate SMTP error codes:

452 4.4.5 Rate limit exceeded. Please try again later.

​
Best Practices

To effectively manage your rate limits:

  1. Monitor Your Usage: Regularly check your dashboard for usage metrics
  2. Implement Backoff: Add exponential backoff when receiving rate limit errors
  3. Queue Implementation: Use a queue system for high-volume sending
  4. Spread Load: Distribute sending across time windows when possible

​
Increasing Your Limits

If your current rate limits are insufficient for your needs:

  1. Review your current usage patterns
  2. Contact [email protected] with:
    • Your account details
    • Current sending volumes
    • Required sending capacity
    • Use case description

Our support team will work with you to find the right solution for your email sending needs.

​
Rate Limit Notifications

You can enable notifications to be alerted when:

  • You reach 80% of any time-window limit
  • You exceed any rate limit
  • Your usage patterns suggest you may need a limit increase

Configure these notifications in your dashboard under Settings → Notifications.

​
Support

For any questions about rate limits or to request increased limits, please contact our support team:

We’re here to help ensure your email sending needs are met while maintaining the highest standards of deliverability.